As I'm on break at work I can't look up my reloading data.

Are the charge weights on or near the "start" levels for the powders you are using?

Sometimes with a self loading rifle using a powder's charge weight on the lower end of the reloading tables will not be enough to cycle the action properly.

 

I started with 42 grains of IMR 4895, then bumped it up to 43, then 44 grains but was still having the very same problem. Tried IMR 3031, which burns a little faster, started at 40.5 grains then 41.5 grains. Accuracy was very good with 41.5 grains of IMR 3031, but I'm still not getting the rifle to cycle.

Since the rifle is fine (commercial ammo functions perfectly) and from data I've read the powder should be sufficient I am suspecting that my brass may be the culprit. The brass is previously fired (? times) that I have trimmed to 2.010 and sized in small base dies.

I've been looking on the internet for dimensional information for 7.62 NATO brass including neck wall thickness but am coming up dry. I'd like to trim the neck thickness but haven't seen any guidelines about minimum wall thickness.

Roudy

 

Your loads are right in the middle of the range for those powders.
A quickie test would be to try increasing the charge (safely of course) and see if it likes those. Try using your old brass as well as the once fired stuff.

I've never had a failure to operate in my Poly but it's not packing the type of chamber you've got.

 

Are you case collet neck sizing the brass or using a full case sizing die on the brass. I was told that the cases had to be full-length sized in a semi automatic rifle, otherwise the bolt might not slam home far enough, or it could go in to far and get stuck causing a majority of the force to go into extracting the case. Just my thoughts, no practical experience as in reloading for a garand so far I haven't had any problem with the action cycling and I'm using starting loads only.

 

I missed your post before mine. I was consulting my reloading manual.

Grab some factory fresh stuff that functions fine in your rifle and pull a bullet or two. Measure the brass and see what you get.

If you've got some original surplus NATO stuff, you can do pull one of them for a comaprison.

See how either one of the unfired cases measures up against yours.
Is it possible that your cases are swelling in the body and sticking in the chamber?

 

Good idea about pulling bullets from fresh ammunition, will give it a try.

I know the chamber is tight, when I first started reloading for this rifle I tried using a Lee collet sizing die and the brass would not chamber. Could only get the brass to chamber when full length sizing in an RCBS small base die.

Roudy

 

Rowdy, Do you have a cartridge case guage? That is the best way to see if you are resizing your brass properly. Moved to ammo forum.

 

No I don't have a cartridge guage, but it certainly appears that I need to get one for 7.62 Nato.

Roudy

 

The cartridge gauge is an excellent idea. I need to get one also.

A question on your reloading set up: When you have your sizer die in the press is it set all the way down or do you leave any sizeable gap between it and the shell holder?

 

If you are small-base resizing, then I presume your case is trimmed to 2.005"? Then you pour powder and seat bullet to 2.800"?
Clean the chamber with the chamberbrush and then a 410ga swab. Using a small drillbit, with your rifle unloaded and the bolt back, muzzle up, check to make sure your gasport is aligned. Search on the forum for drillbit or use 1/16th" or 1/32nd" carefully thru the bottom of the gas cylinder thru the barrel. You should be able to look in the barrel and see it come out the gas port.
If all is well so far, start working thru various factory ammo to see if it all works. If all factory ammo works, then you are not set up right to reload- could be resizing, trimming to proper length or total overall length. Take a step back, a deep breath, and start from scratch.
Good luck and let us know what works.

 

The setup I have been using is the die touching the shell holder. RCBS recommended that I turn the die down another 1/8 to 1/4 turn.

Roudy

 

One needs too #1 resize there brass and then #2 trim thier brass too lenth 2.005 is the min after this a quick check in a case gage. if it's good to go I clean the PP and then prime, charge, and seat bullit. (I like 2.82 for the COAL)

 

I have a suspicion from reading your posts that you are not getting enough headspace clearence with your reloads. Even when the shellholder touches the bottom of the die you may not get enough shoulder setback (.002 - .003) for best function. Part of this is die design and part is from press "spring". If you adjust the die to touch the shellholder (with the ram all the way up) but still see a small gap when sizing a case that is press "spring". I adjust my sizing die down until the bottom goes below the shellholder. But you still need a Stoney Point for an accurate setting. This gap was more obvious with some makes of dies. I use a Forster NM sizer die for my M1A and it has worked perfectly. Shoulder setback will vary between different brands of brass and some individual cases so I mike each one. Any that need more sizing go through a Redding Body Die.

 

One other possible solution I didn't think about - is your gas piston clean? If it's fouled up then the problem could be you are not getting enough port pressure to cycle the action. The factory ammo may be using a slower burning powder which is giving you a little extra gas volume - and letting the gun cycle.

 

The setup I have been using is the die touching the shell holder. RCBS recommended that I turn the die down another 1/8 to 1/4 turn.

Try it my way......

6) I use a single station press (RCBS Rock Chucker). You could use a progressive Dillon IF you wanted to. It's a personal choice. But, with whatever press you choose, consider shell plate/shell holder and/or press "flex.” I use a regular FL size/de-capper die, NOT the small base dies. To begin, FL size and de-cap, 1 or 2 cases for a test. Gauge the re-sized case(s), to confirm that the "correct size" has been achieved. I use a Forster Products case gauge (the Wilson gauge is also a popular choice). Insert a case into the die, the case needs to be between the high and low cuts on the gauge to pass. The base end, checks the headspace, while the other end, is used to check if the case will need to be trimmed (a job for later on). IF, it’s not the “correct size,” your die setting will need adjustment. Lower the ram and simply screw the die in or out a little. Don’t forget about the lock nut. Then, re-size another couple of test cases and check your work again. Repeat the test and adjustments, as needed. When you're satisfied that your test cases are properly re-sized, do the entire lot.

____________________________

For those who don't know about it.........IMHO…………"the secret" to re-loading a bottle neck cartridge for a gas gun is.......a case gauge. There are many different brands and ways to gauge your re-loads.

Examples……..

http://www.sinclairintl.com/cgi-bin/category.cgi?category=REMTHT&type=store

Aloha, Mark

 

This is probably splitting hairs, but...I see on several of the suppliers that I use that they have case length gages for .308 but don't see any listed for 7.62 NATO. Since I have a Springfield M1A and not an M14 will this make any effective difference?

Thanks to all for your time and thoughts. I need to get to work now and get all this sorted out and implemented.

Roudy

 

Roudy,

Please don't forget to update us when you get your reloads working! And yeah, press spring/flex - same thing. I reload for a SAI NM and the chamber has a HS of 1.631.

 

This is probably splitting hairs, but...I see on several of the suppliers that I use that they have case length gages for .308 but don't see any listed for 7.62 NATO. Since I have a Springfield M1A and not an M14 will this make any effective difference?

Say you followed the advice...........

Whether you have a NATO chambered barrel (M14/M1 Garand G.I. ".308 Win."/7.62mm NATO barrels all have NATO chambers), or a .308 Winchester chamber, keep the headspace within SAAMI limits (1.630 GO, 1.634 NO GO, 1.638 FIELD REJECT). This subject is a bit confusing, and for me difficult to explain in a one way conversation!
Clint McKee

So, you used once fired 7.62 NATO brass that is re-sized in a standard F/L sizer die that is marked .308 Win. and you're using a Wilson Case Gauge to test your re-sizing efforts, that is marked .308 Win..........so, the newly re-sized case is for all practical purposes a .308 Win. BOTTOM LINE: Don't worry about it, as long as your rifle's headspace is within spec.

Aloha, Mark

PS.....maybe this will make you feel better.......

U. S. commercial manufacturers typically headspace M14 type rifles to Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI) specifications for .308 Winchester unless chambered for another caliber. However, some U. S. commercial M14 type rifles built by armorers and gunsmiths for competition were headspaced for 7.62x51 mm NATO ammunition. Therefore, the buyer should check the headspace when purchasing a rifle unless the factory or gunsmith supplies the headspace reading at the time of purchase. If the headspace is from 1.630 " to 1.634 ", then either commercial manufacture .308 Winchester or military manufacture 7.62 x 51 mm NATO ammunition can be used. The subject of hand-loaded ammunition in the M14 type rifle is beyond the scope of this work.

If a USGI M14 rifle bolt closed on a USGI FIELD REJECT gage with a FIELD TEST bolt
(drawing 7274799) installed, the rifle was removed from service and the receiver and
barrel declared unserviceable. If the FIELD TEST bolt would not close on the FIELD
REJECT gage but the issue bolt did then the bolt was removed from service and
replaced. The USGI M14 headspace gages were sized as follows: 1.6355 " GO (drawing 7274780), 1.6375 " (drawing 7274782), 1.6415 " NO GO (drawing 7274786) and 1.6445 " FIELD REJECT (drawing 7274790).

 

If you feel you can easily strip and reassemble your bolt, I would suggest you strip your bolt and try manually chambering your resized brass with the stripped bolt.

 

Try small base dies, It solved my problem which is similar to yours.

 

This was a problem for me also until I checked the re-sized cases in a Wilson .308 case gauge. Headspace on my rifle is 1.631. I use a Dillon 550b with Dillon .308 dies (which they say are small base) and adjusted the die down until the re-sized case fits the gauge minimum measurement. This (at least on my press) is far enough down that there is a bit of pressure from the shellplate on the die when the handle goes over top-dead-center. Voila! No more problems with reloads. The final test is to see if they chamber easily and the stripped bolt locks without any effort (also disconnect and remove the recoil spring and guide) but I wouldn't use this measure to adjust the sizing die as the case gauge was designed to give you this measurement. I have only used the Wilson gauge but have heard good things about the Stoney Point gauge.

Eagle 1

 

1. I assume you've checked, and it works fine with factory loads.

2. If you're own an FL or SB sizing die, you ought to have some way to measure the cases your sizing. I like the case headspace gages made by Hornady or Sinclair. These will allow you to measure fired cases and sized cases. You want to set the shoulder back by 0.002-0.004". The Go-NoGo sort of gage sold by Wilson and Dillon work, but they're difficult to take actual measurements with.