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Take that box of 180 grain bullets back where you bought them and swap them for some Winchester white box 147 grain bullets for your M-1A. Conventional wisdom says that you are to stay away from 180 and heavier bullets in M-14's since at they may at the very least end up bending your op rod.

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Discussion Starter · #22 ·
Take that box of 180 grain bullets back where you bought them and swap them for some Winchester white box 147 grain bullets for your M-1A. Conventional wisdom says that you are to stay away from 180 and heavier bullets in M-14's since at they may at the very least end up bending your op rod.

7th
I got'em at Wal-Mart and they have a no-return policy on ammo. I'll have to trade them with a local hunter or give'em away but I won't run them through my rifle. I'll get the white box Winchester, though, if my Portugese NATO rounds are too slow getting here. Thanks
 

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The problem with shooting something like 180 grn winchesters is that this particular lot might be fine but the next may be too hot. Remember they don't use canister powders, they just take the lot they get, run some sophisticated pressure tests to determine how much powder to use and then load them up.

The pressure at the port may vary enough to bend your rod if they go a little hot, or the powder lot peaks a bit latter than the last lot.
 

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That is a vexing question.

Commercial ammunition is not something you control. Commercial manufacturers are free to use whatever components they want, switch them when they can make more profit, and don’t have to tell you anything.

If you have someone out there using the Federal Government to persecute you, then commercial ammunition can be a headache, as this poor man found out:

http://www.falfiles.com/forums/showthread.php?threadid=183318
The rifle in question never doubled on me and I shot it in numerous matches.

The atf got it to double by putting the selector on FA and trying many different types of ammo until they found one with a super soft primer that would double when the hammer followed the bolt home

At the actual test firing that we conducted there were 12 tests with 4 types of ammo and only the Winchester hunting 308 doubled and it did it only twice.

The problem was a worn out firing pin spring.

I never tried to shoot the fal with the selector on FA for the obvious reason of knowing that it could only fire out of battery that to do so would be risking a dangerous outcome.
I also would never shoot expensive hunting ammo $15 a box of 20.

The HTS set (DSA) was not doubling

I work with a Class 2 manf. and I have no reason to shoot a illegal MG we have all the legal ones we could ever need.

The ATF agent that confiscated my FAL's did not do the test he took the rifles to the tech branch in DC where they were "tested"

After many months and $ my lawyer, expert witness and I got to do our test with the ATF and we video taped it and that is when the truth was shown.

A local gun dealer here in NC By the name of Dan D. who for some reason did not like me actually turned the ATF my way by telling them a bunch of lies.

After the many man hours spent on my behalf I think the atf just tried to salvage a conviction of an innocent person to justify all the time spent in their investigation of me.

It is a long story but this sheds light on the jist of it.

I just this week was given back my property except for the one rifle that malfunctoned.

Thanks to diligent work by my Lawyer
I don’t fire commercial ammunition in my M1a’s for several reasons. The first of which, as the savants have mentioned, the first consideration is pressure curve. I don’t want a slow burning powder and magnum level velocities.

The second reason is that I don't have control over what primers are used.

The Army always used the FA34 primer. I found this on page 4-69 of the "Report of the M16 Review Panel Appendix 4 Appendix 4 Ammunition Development Program"

You can find this at http://www.dtic.mil/dtic/index.html.

The Army was having all sorts of issues, slamfires, primer sensitivity, etc, with the early M16’s. The quote from the primer sensitivity section was
“Contrary to the requirements for 7.62 mm ammunition, which specifies that the FA34 primer is mandatory, no attempt has been made to standardize on type of primer for 5.56 mm ammunition”.
This report was before the military required the use of a #41 primer, a less sensitive primer, in 5.56 ammunition.

The #34 primer is a less sensitive primer than commercial primers. This is what you want to use in M1a's and Garands. The least sensitive primer you can find. However, some commercial primer makers, noticeably Federal primers, are very proud to tell you they make the most sensitive primer on the market.

You might get a real sensitive Federal primer in your commercial ammunition.

One of the good things about commercial ammunition is that factory fresh ammunition is always of minimum dimensions.

This guy had a tight case, without a doubt the bolt stopped trying to crunch fit his case to the chamber, he had a sensitive primer, and his gun fired out of battery.


http://www.snipercountry.com/HotTips/Slamfire.htm
M14/M305: I looked at my personal "slam fire" and here is what happend. I have a NM TRW bolt in a Norinco M305, I shot realoads that were made for and previously shot out of my G-3, the local hunting clubs range I shoot at does not allow magazines, or slings,(go figure) to be used.

My conclusion: headspace is really on the tight side after lapping the bolt in, the realoads even though full sized still had the H&K flutes on them and may not have seated all the way in the chamber, I used thin CCI Bench rest primers in tight PMC brass pockets that were seated real flat, and I had to load the round into the chamber and then close the bolt onto it which causes a higher bolt speed forward that if it would feed a round out of the mag. BAM, Slammfire ! Clearly not the Guns fault, but operator failure. The only damage that I found so far is a small deformation in the OP rod cam were the bolts giudewheel runs. I´ll take her to the range again and fire some factory FMJ out of a Magazine to see if the little deburring I did solved the problem.

The straight wall, no neck .308 case is in a special glass case I reserved for little reminders. This case also includes a 1" truck wheel nut and bolt that I stripped. It was stamped L for left hand thread, but in the heat of battle, what do I know.
"Ende"
Torsten <[email protected]>
Germany - Thursday, February 11, 1999 at 08:50:34 (ZULU
If this guy had been using factory ammunition it is likely the slamfire would have been in battery as there would not have been resistance to chambering the round.
 

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The main think to keep in mind on slam fire is that you should just be aware that it can happen so that you can keep the gun pointed downrange.
 

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I had three in my first range visit after buying my new 22" standard. First one was with Remington 308. The second two were with Winchester Fusion 150 gr. 50 rounds of NATO 149 gr XM80 and not a single problem.
NO MORE COMMERCIAL AMMO for me.
 

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I had three in my first range visit after buying my new 22" standard. First one was with Remington 308. The second two were with Winchester Fusion 150 gr. 50 rounds of NATO 149 gr XM80 and not a single problem.
NO MORE COMMERCIAL AMMO for me.
You need to get that rifle checked out by a 'smith who knows his business. 3 slamfires in one day with factory ammo is crazy. Deadly serious here. Call Springfield if you don't have a local gunsmith.

That 50 rounds of XM80 is statistically close to 0; that rifle is dangerous!
 

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Burn rate issues have been discussed a lot here. Do a search and see what you think. From what I have read and the opinions of respected members here, yes the m14 system is more tolerant, but the speed of the impulse is as important to consider as the volume of gas allowed into the piston before the excess bleeds off. That is my simplification based on the info I have seen, if it's incorrect I'm sure someone will adjust me.
I'm wondering about that too. Just how much pressure would it take to really jack up a self-regulating gas system?

I've got 180gr bullets I plan to load in my M1A. I've heard about these bullets being to heavy and bending an op-rod but it doesn't make sense to me. It's the port pressure that will bend the rod and it's the slower powders used to push heavy bullets up to speed that create those higher port pressures, no? Yes? Maybe? If 175gr bullets are safe, what's 5 extra grains really going to do?
 

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There was a reprint of an AR article on slam fires included in the box with my new rifle. I stopped on the way home and bought a box of .308 Winchester SuperX 180gr Power Point hunting ammo, being a total noob and not having read the article.

I don't want to risk using it and intend to wait for my Milsurp to get here, but wondered if y'all can tell me whether it's really risky to use the commercial hunting cartridges.
Slam fire with Winchester factory ammo? Winchester would be out of business if there ammo ""slam fired"" in your rifle.
Now If your going to use this ammo in a M1A there is enough good information out there that says do not use bullets heavier then 175 grains.
 
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