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Precision Reloading for the M1A/M305

20998 Views 42 Replies 17 Participants Last post by  mac1911M14
Thought you guys might like the post I made on CGN. Feel free to make it a sticky for easy reference. Enjoy...In this post, I will try and share my experiences loading for the M305/M1A (refered to as M1A from now on) for maximum accuracy. This is a very unique firearm with its share of quirks and misunderstandings. I will cover the history and the roots of this platform, to understand where the designers were coming from. From there, we will go to testing your firearm, loading for maximum accuracy, and learning how to shoot. I will even throw in my secret technique for match prepping ANY brass. You may not agree with it all, but it all works and works well.

How well? Well, I have been getting sub MOA groups with my accurized box stock M1A from DARK International. Took a grand total of 40rds to get it dialed in. Will get some long range shooting when the weather warms up and will post results and groups.

This info refers to the box stock "accurized" M1A. They come straight from the box pretty loose and unless the rifle is accurized (bedding, unitizing and shimmed gas system, trigger tuning to remove all that creep, solid and rigid scopemount), you will be wasting your time loading. When the rifle is properly bedded/accurized, there will be no movement at all between action/gas system and stock even with very aggressive tugging. The Op rod will slide back and forth smoothly without any binding or rough spots. Grease the moving parts properly. The Op rod spring will not bind or snag - consider a Rooster33 op rod, helps with consistent lockup.

At the end, we are trying to make the M1A run like a bolt action without having to run the bolt. So let's begin with a brief history lesson.

The M14 is a decendent of the WWII workhorse, the Garand. By moving the gas system, adding a detachable mag, and a few other tweaks, the M14 was created to use the smaller but equally effective Winchester T65 round. The Winchester T65 later became standardized as the 7.62 NATO (called 7.62 from now on) and commercialized as the 308 Winchester. The M1A is decended from the M14 by modifying the trigger group for semi auto fire only.

The specs for the 7.62 have been changed slightly over the years but has standardized to the following: 147/150gr @ 2700 to 2750fps (M80); 168gr @ 2600 to 2650fps (M852); 175gr @2500 to 2550 fps (M118). When loading for the M1A, it is best to stay within these vel ranges as that is what the gas system was designed for. Any faster/higher pressure and the problems so commonly talked about occur, plus accuracy is usually horrid. Remember that although the 7.62 and the 308 are dimensionally identical, their performance and operating pressures are not. The 308 is loaded to higher pressures with slower powders. The 308 is loaded for the Sportsman with bolt action rifles, not semi or auto fire battle rifles!!

First Things First!!:

Before we get too carried away with tuning and loading, we have to ensure that the rifle is worth the time. This is a simple test I do with all rifles I work on to test its potential. The heart of any rifle and its ability to shoot is found in the dimensions of the chamber and how true it was cut with the bore. If the bore was cut eyed, there is nothing that can be done to make this rifle shoot.

Start with 5 FL sized new brass, a starting load (ie 40 to 42gr of H335), a suitable primer, and any 150 to 168gr bullet you got. Fire the ammo.

Now examine the brass. The necks should have soot but the neck and case body should be clean. If dirty, increase the powder and try again with new brass until only the neck is dirty. This is the min pressure needed to fully expand the case into the chamber and will be used to determine the bores characteristics and accuracy potential. The brass should be free of any dents, dings or scrathes, looking like it came out of a bolt action rifle.

Now that you have 3 to 5 brass that have been fireformed, measure the runout of the cases. Measure 1/4" from the extractor groove, middle of the case body, and just below the shoulder. You should see runout under 0.005", less is better. Now the critical part. Measure at two locations on the neck. Hopefully, runout will be 0.005" or less. If above these levels, then the barrel will probably only be a 1.5MOA shooter. If there is a visible wobble to the brass, the chamber is eyed and the barrel is hooped. There is very little that will make it a shooter (sub MOA).

If you do not have a runout guage, you can roll the brass over a mirror or flat steel/plastic surface and look for any wobble. Another simple test is to put the brass back in the chamber. It should go in without any problems and will go in even when the brass is rotated then reinserted. If the brass goes in one way but will not when rotated, the chamber is out of round. Could still shoot but loading for this chamber would be a pain with short case life.

Hopefully, your chamber is concentric. If so, try test number two. The second test measures the length of the throat and its relationship to the bullet. If the bullet leaves the case neck before fully engaging in the rifling, that rifle will also not shoot well.

Take one of those fired brass, neck or FL size it and seat a bullet just into the neck. Reinsert into chamber and hopefully it will not fully chamber. This indicates that your throat is short enough for good accuracy. If the bullet cannot touch the lands, then the chances of a shooter is reduced the further the bullet has to jump.

Assuming your rifle passes these two tests, have it accurized/bedded and let's begin loading. Otherwise, know that the rifle might shoot but not consistently in the MOA or smaller. Replacing the barrel with a well cut chamber is the only real solution.

308 Winchester - No Good:

First thing we have to get rid of is most of the reloading data. Simply because it is for the 308 Winchester, not the 7.62 NATO. Also, forget about factory or surplus ammo. Factory ammo is loaded to 308 specs and will really beat up your rifle. Surplus ammo will have casual accuracy at best (3MOA is good stuff). The only ammo worth considering is Vietnam era M852 and M118 sniper ammo. However, since this stuff is rare and probably has collectors value, why waste it.

To load for the M1A, you must balance the harmonics of the barrel AND the pressure curve/timing of the gas system. So that means only a few applicable powders, bullets, primers and brass.


Powders: The best powders for the 7.62 are in the med fast range and include H335, Benchmark, H4895 and BLC-(2). I am not familiar with other brands of powders from Accurate Arms, Reloader, Winchester and IMR so will exclude.

I have found H335 to be one of the best surplus powders to use but it is temp sensitive. That means that loads will have to be adjusted if ambient temp change by more the 5C. Hotter weather less powder, cooler more. BLC-2 also has the same problem. WCC 845 from Higginson Powders would make a great plinking powder. Cheap like rice and it burns pretty well. A bit fast for optimum results but may work ok in other rifles. All ball powders share one unfortunate trait, they are very dirty burning powders. I would clean more often then with the extruded powders. Maybe every 100rds or so.

The Extreme powders from Hodgdon, eliminate that temp sensitivity and as a bonus burn very cleanly and consistently. This makes the H4895 Extreme and Benchmark the powders to use when competing or hunting. I will soon be doing extensive testing with Benchmark as its performance in BR types cartridges has been impressive. H4895 Extreme is a great standby but I prefer the smaller grain size of Benchmark as it would meter easier. Any old lots of H or IMR 4895 may be temp sensitive so keep an eye on that. Either will work well with bullets from 150 to 168gr.

The 308 standby of Varget is NOT suitable for the M1A - too slow, too much gas pressure, too much gas volume. However, reduced loads might give great performance. I just don't see any point in reducing the vels more then I have to.

The loads with the above powders are not whimpy at all. The max pressures are certainly lower then the 308 but not by much. They just burn in a different manner more suited to the M1A gas systems. The damaged op rods and high receiver wear rate/stretching can usually be traced back to using heavy doses of slow powder ie bolt action load data. If doing a lot of shooting, a recoil buffer (Buffer Technologies) is cheap insurance and will soften recoil too.

Bullets: The best bullet weights range from 150 to 168gr. Personally, I like the 155gr Hornady Amax because of its very high BC and excellent accuracy. I have shot it out to 1300m (1450yds) and it stayed stable and accurate.

The 175gr MK is now very common in LR match shooting but unless you modify your M1A to accomodate the heavier bullet and load, the NATO performance is not all that great. At 1000yds, the 155gr Amax will outperform the 175gr MK. In fact, at such a low starting vel, the 175gr bullet may not stay supersonic.
Other excellent choices include the 150gr Hornady FMJ BT, and poly tipped hunting bullets like the 150gr Hornady SST and Nosler BT. The 155/168gr HP match bullets from Sierra or Nosler are also suitable but with their lower BC, they are just not as good when ranges extend beyond 600m.

Forget about any surplus or pulled bullets, even "match" ones. They are simply not capable of shooting consistently in the MOA range. Garbage in, Garbage out.

I moly coat my bullets and it works for me. Uncoated bullets work just fine and in the chrome lined barrel, fouling is light anyways. I don't wax my moly bullets as I am concerned about fouling issues with the wax. My hands get dirty but they shoot well so I don't mind.

Primers: The best primer I have used is the Fed 210M. It is not a soft primer and I have not had any problems with slam fires. Another great choice would be the CCI BR2. Match primers do make a difference when distances get long or when accurate shooting is what you are after. Unfortunately, my favorite non match primer, the Win LR, slam fired quite regularly and has been dropped. May work in other rifles.

Speaking of slam fires, there are a couple of solutions. Increase the primer seating depth to max SAAMI depth using a LYMAN pocket uniformer, use a "tougher" primer like the Fed 210M, or play with the firing pin return spring. Oops, it doesn't have one - any enterprising machinists out there want to come up with one?

Cases: By far the best commercial case are those from Winchester. After all, they did design this round. Many service rifle shooter use this brass and it is consistent and durable. Fed Gold Medal brass is next up. Heavier and thicker then Win, it holds less powder so back off loads with this brass. Very nice stuff. Surplus NATO brass follows. For those, concerned that surplus brass doesn't shoot, all I can say is my smallest group ever fired was with surplus NATO brass. I will discuss latert how to get the most from your brass.

I wouldn't bother with "match" brass like Norma or Lapua because these are at least double the cost, usually softer and may not last as long. We are not shooting a BR rifle where a few thou matter.

Brass Prep: Now that we have our new cases, what do we do with the? I start by deburring the flash holes using a tool from RCBS. The brass is then loaded with the starting load you found in the testing stage and fireformed. Examine the brass. There should not be any scratches, dents, shiny spots on the surface. Primers should be well rounded, not flattened.

Try putting the brass back into the chamber. It should fit smoothly and easily - perfect. Now comes the most controversial part...Sizing.

Sizing Your Fireformed Brass:

A lot of misinformation is out there about sizing fired brass and is the single largest cause of problems with head separation and short case life. This is the same problem faced by those who load for the belted magnum cartridges, and the solution is the same for both. But first let's define a few terms so that we are all talking about the same thing.

Headspace is a measure of the difference in distance from a datum line on the shoulder of a bottleneck cartridge to the rear face of the cartridge and the bolt face. Basically, what we are concerned about is the gap between the back of a fully chambered cartridge and the bolt face. Less is better as long as it does not interfere with chambering. Why do we want this? Because during the firing process, the firing pin drives the case forward till it can't go further anymore. The pin then compresses the primer igniting the load. Under pressure the case expands to fill the gap (headspace) and stretches.

Why Full Length Sizing is Not Always Best:

If you were to now FL size the brass andmove the shoulder back to min.dimensions, the next time you fire, the case will stretch again. This causes enormous strain on the web or head of the case and will eventually lead to case separations and other nastiness.

There are two solutions: reduce the headspace so that FL sizing will work. Problem is that FL sizing dies can introduce a fair amount of runout in the brass which is not good for accuracy. Also, you must get the die and chamber dimensions to be within a few thou. That is also not easy and will require a lot of parts swapping or custom dies. Both are very expensive.

The second is to work with the fireformed brass and the chamber/headspace you now have.

When you work with fireformed cases, we are working with cases that has essentially zero headspace. This reduces case stretching and the chance of head separation. It also is in perfect alignment with the bore (remember the runout we were measuring at the start). The ensures a straight start for all those expensive bullets.

All rifles have varying amount of headspace and differing chamber dimensions, even BR match rifles. So when sizing, we want to minimize any change in case dimension which can affect case life or accuracy. The best part is that the actual chamber dimension no longer matter. We are forming brass to fit whatever the chamber dimensions are, even something that would swallow a no-go guage. The cases you form are a custom fit to that chamber alone. Don't bother using someone elses ammo and certainly never share ammo. Just think of it as having a custom chambered match rifle.

Neck Sizing:

So how do we size the case and maintain all that wonderful alignment and fit? We neck size. "But the cases won't chamber" BUNK. You just proved it when you pushed the fireformed case easily back into the chamber. "But the cases will grow too big and jam later" BUNK. At the reduced pressures of the 7.62 loads, good quality brass will survive many firing before there are any fit issues. I am using brass that has over 8 high pressure 308 firings BEFORE going into my M1A. This brass has been shot another 5 times with no chambering issues at all. I can use light finger pressure to chamber the fired brass. Awesome.

Today, there are only two types of dies that are worth using: the Lee Collet Neck sizing die and a bushing die from Redding or Hornady. Forget about the common neck sizing dies from all companies. You run a very good risk of making runout because of the expander ball and decapping rod. Sometimes the rod/ball are straight, most of the time they are not.

My favorite die is the Lee Collet neck die. It works great, affordable, and sized cases have virtually no runout. Once you use this die and see what it can do for your loads, you will switch over everything you shoot!!.

Trimming and Final Prep: Now that all the brass is neck sized and deprimed, I run them through a trimmer just to square up the necks. Not a big deal but I like square necks...looks more accurate. The neck is then inside and outside deburred and chamfered.

If you are experiencing slam fires, now would be the time to lower the primer pocket to max SAAMI depth. I like the Lyman pocket uniformer tool. Just takes a few seconds per case.

Neck turning is next and is really optional. With a chamber with such generous neck dimensions, it really doesn't matter. However, since we are going for "match" prepped brass, if you got the tools, what the heck. At best, remove no more then 60% of the circumferance. Leaving necks too thin will allow them to split prematurely.

If noticing neck splits, annealing the necks might help. But if you turned them down thin, toss them.

Prime the brass and WEIGH the powder charges. I have found the M1A to have a very narrow sweet spot. Work up the loads in ½ gr increments. Groups will shrink and expand within a half to one grain change of powder. Once a good load is found, a powder dispenser can be used to speed up reloading. Just be sure that charges are within +/- 1 tenth of the target load.

If using a ball powder, loads will have to be adjusted up or down depending on temp and humidity changes. That is why I will only shoot Hodgdon Extreme powders when the shots matter as in competition or hunting.

Cartridge OAL is easy. Seat the bullets to the longest length that will fit in the mag. The throats are long enough that a "hard" seated cartridge so not happen. That was checked in test #2. As to seating dies, just about any die is fine. The runout caused in loading usually happens in the sizing stage. Very little problems are caused in the seating stage but check just to be sure.

The ammo should be as close to zero runout as possible. Ammo with more then 0.005" of runout is not going to shoot consistently MOA or under. This applies to all ammo.

Shooting the M1A/M305:

In order to get the best accuracy, we need to shoot off a solid bench with good front and rear rests. A rolled up blanket on the hood of a truck is not going to work. A concrete or heavy wood bench, a pedestal front rest with rabbit ears bag, and a rear bag with rabbit ears will help with consistency.

Sorry, but I don't consider a bipod a good rest for developing a load. They wiggle and bounce too much. They make for a great field rest but not for load development.

When shooting strive for consistency and repeatability, not speed. The hold, eye position, breathing, trigger control, follow through are all part of good groups. If unsure, go get some help from a BR type shooter.

Because the M1A does bounce around during recoil, I have found that holding under the receiver with the left hand helps smooth things out. Just use even and consistent pressure. Also, I rest the rifle as far forward as possible to reduce the amount of jumping. I set the front rest so that the front swivel touches the rear of the bag. This helps being consistent when setting up for the next shot.

Mount a solid and secure scope base and use a good quality scope. My eyes just won't see accurate enough for MOA type groups using open sights. With a scope, I want to be able to define at least 1/8" at 100yds, preferably less. Buy the best scope you can afford.

The groups will quite large, then shrink, then grow again. Good groups/loads tend to be where the velocities match the NATO specs. That is why shooting over a chronograph will speed things up greatly. Because the loads are at NATO vel and pressures, the cases should not show any dings or dents. Feeding and extraction should also not have any problems.

Reshoot the loads that show promise then move out further. If this is to be a Long Range shooter, then shoot and test at long range. 100yds groups tell you exactly that...100yd performance. They do not represent what will happen at longer ranges no matter what the math suggests.

I have found many loads that shot in one big hole at 100yds that wouldn't stay on the paper at 500yds because of stringing. Shoot at the furthest range expected and tweak the loads to match that performance. It may not be the smallest 100yd group load!!!

How to Match Tune Your Brass:

Here is my way to get match performance from any brass. I use this technique to sort once fired, surplus brass, and mystery gunshow stuff. Always sort by headstamp.

Fireform and prep the brass as described earlier. Load with your accurate load. Then test fire. As long as conditions are calm and good technique used, any shot that is a flyer is suspect. I mark that brass. Usually firing again will cause a flyer again. Toss the brass.

The brass remaining will shoot consistently into the same group, NO FLYERS!!! This is truly match brass. Forget about weighing and other such nonsense. Only small consistent groups will tell that the brass is up to the task.

Sort, through firing, enough brass to meet shooting needs. It is more time consuming but performance is guaranteed and we all could use the extra trigger time. The competitive shooter will know that each cartridge is as close to identical as humanly possible. Gotta be worth a point to two.

Well, that touches the surface of precision loading for the M1A/M305. I hope that this information will prove useful and that more of these wonderful rifles will start shooting to their potential. Even with paying for the accurizing and tuning done (which I can offer), we are able to own a great shooter for about ½ the cost of a Springfield.

If there is interest, I will post more thoughts on other topics including optics, rifles and reloading for 1000m shooting, stock bedding, and shooting techniques.


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Fairly thorough (about as well as one can be without spending a fortune in different powders) and interesting analysis! Thanks for taking the time to post it! I particularly like the focus on run-out.

The Kuhnhausen manual has a pretty good section on primer pockets and he recommends that you uniform them to a particular depth (can't remember off the top of my head what that number is though).

I find that different primers will handle pressure differently, so I'm not too alarmed if my primers look flat (which they usually are) or even a little cratered. It does cue me to take a look at what I'm doing, check for other signs, etc.

I FL resize to the max SAAMI spec (the least amount of shoulder set back that will chamber under fingertip pressure with my stripped bolt). Can't afford to take a 10 point hit on a match and brass isn't all that pricy, so I don't mind wearing it out sooner. I don't have a run-out gage, but some work with a micrometer shows that I seldom get more than 0.001" at the neck and almost none at the case head. Those are my dies, though.

For those of us on this side of the border, 5C = 9F degrees.

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Accurizing and Trigger tuning

As part of enhancing the hobby up North, I offer an accurizing and trigger tuning service for the M305/M1A's. If there are Canadians on this board who are interested in getting the most from their rifles, send me an email at [email protected].

For the Southern neighbours, trigger tuning is available. It is essentially a National match trigger job. I eliminate all the creep. Maintain the two stage pull and keep the pull weight near orig. If using in service rifle competition, then will hold 4 1/2lbs at least.

Can't offer much for bedding, gas system unitizing, rear lug work since getting the firearms up here would be a big pain.

Anyways, if there is anyone interested, my email is there.

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Ok I'll bite. So you are saying that winchester brass, wich is notorious for leaking, loose primer pockets is the best? Not to me. I know military brass isn't the best but it's strong. It can be prepped well and made to work ok. Norma and Lapua are real good brass manufacturers at least for me. Especialy norma! Extremely consistent, good durable brass. It is expensive though like you said. I do my best to always use military match brass for the m-1 and m-14. I am currently using a batch of LC-91 wich is M-118 polldown brass. It isn't very consistent and the primer hole is full of burrs and the crimp has to be dealt with. But after a little work it is very good stuff. I even go as far as weight segregate it into buckets and keep my boxes of reloads out of the same weight batch. It makes a difference on those far off ground rats we call prairie dogs.
You also recommend to neck size. I hope you got good liability insurance! I would never recommend that to anybody. It may work fine on a perfectly clean rifle under ideal conditions but out in the woods or on a firing line it isn't worth the risk. I experimented with neck sizing before. Not with a collet die like you use. Just the standard old rcbs. It worked sometimes and others it didn't. I found myself lookig down at the bolt more often than I should to make sure it locked in. Not a good thing to pull the trigger and not hear it fire. Thank god for the safety bridge!
I , like 30cal, size to my chamber. No more. No less. It works just fine and I too get very consistent sub moa groups. My rifle prefers a 168 jacketed and a 170-175 cast bullet. Btw the m-14 is an awsome reduced load cast bullet shooter! I run mine about 2000 fps and never had a hiccup.
I hope I don't come off like I am getting on you. I just don't agree with some of it and I have been reloading for the m-1 and m-14 a long time. You do have a lot of good advise though. I just can't recommend a potentialy dangerous practice in public when a novice reloader may read it and take it as gospel then go out with a box of freshly necksized rounds, a filthy chamber, and rusted bore and blow is head off when it fires out of battery. You will not beleiver the number of guns I see in that condition!
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My .02
If you are neck sizing for an m14/m1a you are just asking for a kaboom. Neck sizing is fine for bolt rifles but never in a semi or full auto rifle. Not to mention the feeding problems and magazine problems it will cause. Unless your talking of single feeding them in the chamber and dropping the bolt which IMHO is another form of insanity. One has to remember that this is a gas operated rifle and not a bolt when it comes to reloading.
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Well, that is my point. This is not a bolt action rifle and neck sizing can work. I think if you read my post again, you will not that

1) I am only suggesting this for New M305/M1A. Any rusted bore, pitted chamber battle axe has its own levels of concerns no matter what the ammo used is. A rifle is such disrepair would be even more dangerous if someone went down to wally land and picked up a box of factory min SAAMI sized 308 ammo and went shooting. At those elevated pressures and a poor rifle, you bet, Kaboom is definitely a possibility. How about including larger then spec headspace? Receiver stretching? Cracked bolt lugs?

2) The loads are at NATO specs so reduced pressures relative to the 308. Makes a huge difference in brass life, stretching, etc. I have had wonderful success with Win brass as have others. This batch of brass was used in my bolt match rifle at very toasty pressures (certainly above SAAMI spec) and the primer pockets stayed tight. Now that same brass is in my M305 and working just fine. Lots of brass do vary so maybe you were running a bad batch or overpressure or oversized chamber or why.

I also use Lake City brass and with my brass prepping technique, get match performance. My experiences with Norma is that it does not stand up to the repeated use of high pressure loading. Again, I may have had a bad batch but ...

3) Interesting point about neck sizing and not chambering fully. As mentioned in my post too, there is a need to check to ensure that the brass with chamber with light finger pressure. This ensures that the ammo will chamber properly and fully. So if the checks are done, there is LESS risk of Kaboom then when FL sizing and oversizing. FL sizing has probably done more to cause head separation then anything else.

The same Newbie reloader not understanding headspace and setting back the shoulder too much could be at greater risk by FL sizing. Case separation would occur. Not IF, but WHEN. If a reloader does not understand realoding, any rifle can be a bomb waiting to happen.

When I started the post, I did indicate that the info was for those interested in Accuracy not in the mud functionality. Match shooting is where the above loading techniques will show the biggest benefits. Certainly, not on the battlefield, but then again M80 don't shoot so good.

I also stated that some of this info would be controversial. I have read from so many people that only FL sizing will work. As mentioned above, without an understanding of case size, load pressures and its relation to Kaboom, that advice is just as dangerous.

When the steps and checks I mentioned are adhered to, Neck Sizing is indeed a safe method of loading an M305. However, as is said in all reloading manuals, since we can't control what someone does or doesn't do properly, the users accepts all risks and responsibilities for the use of this info. Are the lawyers happy now?

For those who are experienced reloaders looking for a way to improve performance and brass life, try the above. Seems to work, and work well...

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Re: Accurizing and Trigger tuning

mysticplayer said:
As part of enhancing the hobby up North, I offer an accurizing and trigger tuning service for the M305/M1A's. If there are Canadians on this board who are interested in getting the most from their rifles, send me an email at [email protected].

For the Southern neighbours, trigger tuning is available. It is essentially a National match trigger job. I eliminate all the creep. Maintain the two stage pull and keep the pull weight near orig. If using in service rifle competition, then will hold 4 1/2lbs at least.

Can't offer much for bedding, gas system unitizing, rear lug work since getting the firearms up here would be a big pain.

Anyways, if there is anyone interested, my email is there.

Hi Jerry, While I appreciate you letting everyone know about your services, it would be better in the future if everyone would post their services, and items for sale in the PX forum.....Thanks, The R.O.
Will do

Hawk, thanks for the heads up. Will post there in the future when offering services...

Re: Will do

mysticplayer said:
Hawk, thanks for the heads up. Will post there in the future when offering services...

Yer welcome :mrgreen:
These are two minor points but I thought the changes from the M14 to the M1A were modification of the receiver not the trigger group. Also, the .308 Winchester and the 7.62 NATO cases are not dimensionally identical. Kuhnhausen writes for a .308 Go Gauge headspace is 1.630, for a 7.62 Go Gauge headspace is 1.634.
Splitting hairs

The go guage lengths are within 4 thou. The allowance before trimming is 10 thou, and the actually chamber depth cut can vary even more.

So for all practical sense, they are dimensionally the same. Certainly, their dimensions overlap within their tolerance range.

Of course, there are significant difference in neck diameters and throat dimensions but that is a function of application.
Military brass for a military rifle period. No exceptions. But thats only my rule. Also 1 reloading for once fired brass then it is tossed or used for my bolt rifle which is another one of my rules. Brass is cheap, my gun and my safety is expensive. But I am surprised that you did not get into primers. This single item is probably cause for more kabooms than anything else either by using too soft of a primer or seating problems.

Actually, there is a fair amount of info on primers, seating depths and how to avoid slam fires. Just look in the component section. I have had success with Fed 210M and unfortunately slam fires with Win LR. CCI BR2 is also an excellent choice.

Only problem with using brass once is you never get a chance to match them. The potential for improved groups with prepped brass is increased.

As you said, its a personal thing. Be safe, watch for any pressure signs and signs of case separation (shiny lines near the web). With my suggested sizing method and NATO pressure levels, brass life has been great.

Your mileage may vary...

:roll: Winchester Brass?? 8O :roll: :? Necksize only? SURELY YOU JEST? I hope you stay around shooting with us for a while. :wink:
I was wondering when you were gonna see this trungsi. :lol:
mysticplayer I just had to chime in on this one, personally
I would not even consider neck sizing for a semi gas gun, in a
bolt rifle for accuracy, I'd give a nod. Insofar as Winchester brass,
good stuff but, it's the thinnest walled brass out there, I can't
get more than 3 reloads from it, however, it is great in a .223
mouse gun, I can get more volume in the case and get 5 reloads
in the AR with Winchester. As for primers I use WLR for both
the M1A and the AR with zero problems, I only use the 210M in
my long range bolt guns. I guess each to his own, I'll stick with
keeping my body parts as they are. :roll:
Been watching this thread for a while and the back and forth banter about 2 different philosophies about sizing M14 brass. Here's my $0.02 :wink:

For a military battle rifle, I would never consider neck sized ammo if the shooting conditions are combat like, i.e. there is a lot of dust and crap floating around, ammo can pick up dirt and grime, etc. Also, if the weapon can be fired full auto, i.e. the M14, I would want a very generous chamber to accomodate dirt and dimensional differences in cartridges.

However, I suspect that most of us (95% or so) fire our M1As on a nice clean range. The chance of picking up a load of crap on our ammo is vitually zilch :) . In that case, I would look for a NM type chamber (headspace of 0.001 or less). We all know, that this is desirable for match shooting. Well, funny enough, that's what we can achieve as well by neck sizing for a more generously headspaced chamber.

I have never heard that makers of NM M1As have been sued because their rifles go KABOOM. So, IMHO, I don't think this would be a problem with neck sizing either. If the case seats all the way into the chamber and the bolt is fully in battery, there should be no problem. BTW, the M1/M14 bolt is designed so that if the bolt is not in battery properly, the hook on the rear of the firing pin does not line up with the slot in the receiver bridge underneath the bolt. This prevents the firing pin from traveling fully forward, preventing striking the primer. This was designed by John Garand as a safety measure to prevent the rifle from firing when the cartridge was not fully seated into the chamber.

I also shoot an AR15. I routinely use full power, neck sized cartridges in that rifle. I have shot a few thousand rounds that way now and have yet to experience a misfire or jam. Neck sizing in my TRW M14 works quite well too. I haven't fired quite as many rounds through it as my AR, but have so far not experienced any problems either.

I agree that military cases are best in the M1A or any other MBR. The semi-auto function of the rifle is harder on the brass than a bolt action rifle, so I would want to have the strongest brass available.

Well, back to you guys, Rifledude signing off, over and out...
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Flat earth

The earth used to be flat and the center of the universe.

I figured there would be a lot of resistance to this info. After all, it certainly goes against the norm. but then the norm on this board is different from the norm on others.

folk lore become urban legend become fact. I guess it just depends on your view of the world.

for those willing to look beyond the horizon, give it a try. Do the tests for chambering and there will not be any problems. Yes, even with Winchester brass.

I am amazed at the amount of dislike for this brass. From all the other US shooters service rifle shooters I converse with that use Win brass, you would think there would be some respect for this brand on this forum.

For the person that was only getting 3 reloads with the Win brass, I bet the problem can be traced back to oversizing the brass. This is a problem when the FL die is not an exact match to the chamber. As the previous post said, whether neck sizing for an expanded chamber or FL sizing that fits the NM chamber, what is the difference. The brass is sized to retain its fit in the chamber.

I think many who believe FL sizing is the only way don't really understand the relationship between brass size, chamber dimension and the internal dimensions of the die. Without this understanding, FL sizing is much more dangerous because head separation will occur. Also, during ejection it would be very possible to tear the rim portion off and cause a class 3 jam.

Military brass, commercial brass, match brass. I sense a true lack of knowledge on reloading. So I agree that you should use the toughest brass you can. PS there are many who consider military brass to be brittle and dangerous. Just goes to show...

anyhow, the info is there for those who choose to expand their horizons.

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I can account for over 50,000 reloads I have done just for my m-14. In that time I have never had a head sep or a split neck or any other major problem. I have pretty much always gone 6 times on a case too. The problems I have with win brass are the same as with federal. Loose primer pockets. I don't overload the charge and don't do anything else that can cause it but It is really irritating seeing the black ring around a fired primer or a pitted ring around my firing pin. This is the one and only reason I stick to military brass. I have yet to see it occur on Lake city. I have seen loose pockets on IMI but only on the 4th or 5th load. Still not acceptable really. As for what you say about head seps being a direct result of poor reloading practices I totaly agree. I just don't agree with your cure. Not to say you are wrong and I am right. I just think that full length , or partial resizing in some guns, is a safer way to do ensure the case will fit the chamber properly. This is where the problems occur though. A lot of people these days don't read instructions. I am guilty of it all the time. The people that do read the die set up instructions that came with their dies will never try another way. You know most of the manufacturers recommend sizing to minimum dimensions. This is just not good. I have different die sets for every different gun and all of them are adjusted to size to the chamber. I check it periodicaly and rarely have had to make adjustments even when using brass of another brand. One exception is once fired machine gun brass. That stuff I rarely use but it needs sized further down usualy and I have another die set up just for it.
With my match douglas heavy barrel I have tried neck sizing and yes it did work but when I try to chamber it with a stripped bolt by hand it doesn't. I just don't see that as safe. the force of the bolt can and usualy is enough to chamber it but what about that off chance that it doesn't and it's a gun where the firing pin bridge is out of spec or just worn out? could be bad.
different people different opinions. :D
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:D mysticplayer! Idont like Winchester Brass for the following Reasons: sloppy Primer Pockets, thin , light Brass leaving too much dead space after you add Powder, I am not sure how that affects pressure or accuracy. We all know that the M-14 jerks on Brass worse than any other Rifle, therefore I'd rather stay away from it. As far as Necksizing only: I have witnessed TWO out of Battary explosions first hand and I'd rather not have one :cry: So therefore I will continue to FL size Thank You. 8)
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