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Old October 9, 2022, 08:55 PM   #1
smleno1mkIII
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Why is LC 68 M2 Ball so poor quality

Only getting 2590fps average ranges from 2510-2670 shooting poor groups like 6MOA in a Garand that usually does 2.5 MOA or better with anything else I,pulled 10 rounds and the powder charges varied from 44.8gr-43.7gr average was about 44.2gr some rounds seemed to barely cycle the action, shouldn’t the charge be more like 48 gr and velocity be around 2805-10fps.
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Old October 10, 2022, 09:38 PM   #2
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Cartridges of the World give the spec for M2 ball as 2740fps +/- 30 @78ft.

Powder charge depends on what powder was used and there are several different possibilities.

1968 was a while ago, no telling what storage conditions the ammo has been through (looks won't tell a lot) and its possible the powder has deteriorated a little. Possibly not enough to tell with a visual inspection but enough to lower the velocity a bit.

Additionally, by 1968 the .30-06 had been retired from US military use as a primary rifle and machinegun round for some time.
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Old October 10, 2022, 11:23 PM   #3
HiBC
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Beware if powder has deteriorated it may become corrosive.(To your bore)
Over time it may weaken the brass.
Lets see....68 till 2000 is 32 years then 2000 till 2022 is 22 years so its 54 years old.
Could be it was fine ammo when it was made.

Last edited by HiBC; October 12, 2022 at 12:25 PM.
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Old October 11, 2022, 11:10 AM   #4
Jim Watson
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In 1968 we were in the M14 - M16 era.
Maybe they were just slapping some .30 together for a particular requisition and didn't care about quality.
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Old October 11, 2022, 09:44 PM   #5
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'68

I'm thinking the only M1's seeing much combat in '68 would have been in the hands of the ARVN, if in fact they were using many at that point. National Guard units would have still using M-1's in '68. The Kent State episode had lots of pics with M-1's in he hands of the Guard, that was '71.

You'd like to think that quality control was good at any arsenal, regardless of destination........deteriorating condition seems a distinct possibility. Who knows how 50 yr old ammo has been stored.
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Old October 11, 2022, 09:47 PM   #6
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oops

Okay, that was awhile ago.......Kent State was 1970
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Old October 12, 2022, 12:36 PM   #7
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There was an article I remember reading back in the early70s about "4895 25 years later.

The Author bought 100lbs (4 25lb caddies) shortly after the end of WWII. He used one, but the other 3 got stored in his family's barn in PA and he didn't get back to them for 25years.

The powder was still "good", and usable, but velocities were 100fps lower than they had been back when it was "fresh".

25 years in a PA barn, pretty warm in the summer and quite cold in the winter. Think that might have had some effect???

I do.
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Old October 12, 2022, 08:40 PM   #8
smleno1mkIII
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It did look like delinked MG ammo but even so the charges seem low a lot of stuff I’ve shot is a good deal older than that but it’s usually way more consistent and way more accurate ,and most M2 even WW2 dated stuff gets about 2790-2830 average in this gun.the gun has a new 1-65 SA barrel on it shoots almost anything well except this stuff ?
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Old October 12, 2022, 08:49 PM   #9
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Plus That’s the lowest charge average I’ve ever seen in M2 ball in all the different ones I’ve pulled over the years averages are usually 46.5gr -50gr, 44.2 seems pretty light that’s even a low charge for 3031 which is a fast powder.
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Old October 13, 2022, 06:09 PM   #10
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If you have the lot# and can find someone with access to the records (assuming they still exist) you could find out what powder was actually used and what the charge was supposed to be.

Without that, its all guesswork...

Remember that the arsenals run powder by the box car load, stuff not always available to the public, and stuff that can vary quite a bit from batch to batch. Each lot is tested, and charge weights are adjusted to the characteristics of the powder on hand.. . 50gr might be the charge for one lot, but an identical looking powder might use 45gr in the next production lot.
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Old October 15, 2022, 03:54 PM   #11
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I understand it’s not canister grade powder but the powder definitely looks like 4895 anyway I loaded some canister grade powder to the same charge as an experiment yesterday and guess what almost identical results the velocity’s were within 30-40 FPS different yes but not by much, but this leads me to believe the ammo was downloaded on purpose I’m just trying to figure out why?
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Old November 1, 2022, 10:51 AM   #12
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Does your barrel have the exact same bore, groove and chamber dimensions as the one used at the ammo plant testing their ammo?

https://en.wikipedia.org/wiki/7.62%C3%9751mm_NATO

I've seen several people shooting the same rifle and ammo have a 50 fps spread in average muzzle velocity.

Last edited by Bart B.; November 1, 2022 at 11:13 AM.
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Old November 6, 2022, 06:42 PM   #13
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Couple problems with the late 60s ammo.
There was a shortage of the required powder.. either 4895 or WC 852 etc. Lake city got Canadian CMR 100 powder and worked up loads for it.

I was like you..this stuff is junk because I got low velocity etc.
However when ran through a proper test barrel the velocity was in spec. CMR 100 is very 3031-ish and has higher chamber pressure but lower port pressure. Hence it's also some of the weakest ammo. Worn bores tend to show more velocity loss.

M2 ball loads can be from the mid 40s to nearly 60gr of powder.
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