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Discussion Starter · #1 ·
Yesterday I shot 6-rounds through my 2A1. Five consisted of 155gr Nosler CC and 42gr of IMR 4895 and one consisted of 42.5gr of IMR 4895. With 42gr the cases were very hard to extract. With 42.5 I feared the case would tear out at the rim, or break the extractor. a couple of the cases had flattened primers, and I quit shooting. The cases used for this shoot were Remington, the primers were CCI #34.

I loaded per the Nosler manual, and 42 - 42.5gr fell to a median range.

Since then, I have found that the 2A1 may prefer a Lake City case with a reduced load of 38gr if IMR 4895.

Does anyone care to share their experiences loading for the 2A1?
 

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Stiff extraction is a warning of high pressures so I would seriously back off from that load. Its not the strongest of actions . I have had GI Nato ammo do that and no longer shoot it in my 2A1. I shoot reloads in mine and they are mild.
 

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Good that you paid attention to the warning signs of high pressure.

You might also consider starting your reloading efforts at the bottom end of the recommend (published) load, and work your way up. Don't start half way or full on load.
 

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Discussion Starter · #4 ·
Stiff extraction is a warning of high pressures so I would seriously back off from that load. Its not the strongest of actions . I have had GI Nato ammo do that and no longer shoot it in my 2A1. I shoot reloads in mine and they are mild.
I'm looking at LC cases and a starting load of 38gr of IMR 4895. But until I get home and look at my reference manuals again, I cannot confirm the recipe.

Good that you paid attention to the warning signs of high pressure.

You might also consider starting your reloading efforts at the bottom end of the recommend (published) load, and work your way up. Don't start half way or full on load.
I had actually loaded the rounds for a diffrent rifle, which I sold. Since the 42gr fell into a median range on the Nosler manual I deemed it useable. Bad decision all the same. You are correct, I should have used all three of my manuals to get a better starting load. (Hornady; LEE & Nosler)
 

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Did you trim the cases to the proper length? Too long of cases can create high pressure also. 42gr of 4895 should be well within the safe range of the 2A series. I shoot NATO spec ball out of mine with no problem. 38 gr is more like the load for a .300 Savage
 

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Discussion Starter · #7 ·
Did you trim the cases to the proper length? Too long of cases can create high pressure also. 42gr of 4895 should be well within the safe range of the 2A series. I shoot NATO spec ball out of mine with no problem. 38 gr is more like the load for a .300 Savage
I pulled down the remaining loads, and adjusted the powder to 38gr which is near Hornady's minimum (37.7) for 155gr. While the cases were empty, I checked the length and found that all of the cases fell within the 2.015 limit. To rule out case length as an issue, I trimmed all of the cases to 2.005.

The case that was hardest to extract measured 2.033 after firing. Assuming this case was within the 2.015 limit, it grew quite a bit.
 

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Discussion Starter · #8 ·
These rifles were built to use the 144gn nato round.
I had thought some were even 147gr. There is another issue with the rifle itself. The rifle has a very tight chamber for a NATO chamber. I only have 308 head space gauges on hand, and the bolt will not close on a Field gauge which is 1.638"

Saami 308 WIN
CO 1.630
NO GO 1.634
FIELD 1.638

7.62 NATO
GO 1.6355
NO GO 1.638
FIELD 1.6445

The chamber would seem to be within limits. Regardless, with my cases trimmed to 2.005 and loaded with 38gr of IMR 4895, I should be safely shooting to 2400fps. I will set up a chrony this next round, and see where I am at.




 

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Discussion Starter · #9 ·
I hate to beat this, but I have a related question regarding the extractor on the 2A1, or any SMLE for that matter. While checking out the receiver, I tried slipping in a sized, but unloaded case. I closed the bolt, and when I tried to extract the case, it resisted as though I had fired a round and it had swollen. It seems that huge extractor is forcing the case against the far wall creating a huge amount of friction... I do not see how anyone can speed shoot this bolt with any degree of success. Is it possible I have the wrong head or extractor for my rifle?

Here is an image of the extractor, and you can clearly see the extractor forcing the shell to the back of the receiver. Is this normal? The drag on this empty was just like pulling an over pressureized case:

 

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Take the extractor and spring out there may be crud in there. You need a Indian or Military guage not SAAMI they are different. Are your cases new, fired in another chamber, FLS then loaded.
 

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Discussion Starter · #11 ·
Take the extractor and spring out there may be crud in there. You need a Indian or Military guage not SAAMI they are different. Are your cases new, fired in another chamber, FLS then loaded.
They may be spec'd differently, but the bolt is still not going to close. Look at the NATO specs I posted. The NATO NO GO is 1.638, and my bolt would not close on it as the NATO NO GO is the same as the Saami 308 Field spec.

Saami 308 WIN
CO 1.630
NO GO 1.634
FIELD 1.638

7.62 NATO
GO 1.6355
NO GO 1.638
FIELD 1.6445
 

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Your extractor looks quite correct (or at least, it is the same as the one on my 2A1!)

The case gets pushed over to the left so that it will eject - the friction of the case base against the receiver wall helps fling the empty out of the action.

That being said, I too have found the 2A1 action much "stiffer" to operate than .303 SMLE's.
 

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There are some 12+ Nato specs for headspace on the 7.62.
Many firearms has a different specification.
Which rifle are the figures you quoted based ?

The actual headspace spec for the Ishapore 2A1 is :

The CHS for an Ishapore 2A1 is (They call it LOW) is GO 1.633" and HIGH or NO-GO is 1.642.

(information from the Indian Liasion Officer to Peter Laidler)

The other point in question is that the headspace measurement is taken at some random point on a 'slope', (where a rimmed cartridge is obviously much easier as the space between the back of the chamber and the front of the bolt head)

The fact that it would not close on your 1.638 (well between the Go & No Go dimension) tends to support that the theory of the dimension being taken from a different datum point

As Peter Laidler pointed out in one of his 'lectures' on headspacing a 7.62 if the Win 308 headspace is taken even a fraction of a millimetre in a different postion on the 'slope' than it will have a different measurement to one taken in the correct 7.62 position.

Also there is a 13 thou difference between Commercial and Mil spec chambers.




You just cannot use 308 gauges instead of 7.62 gauges.
I'll try and find PL's notes :

Anyone for 7.62mm CHS?
Posted By: Peter Laidler
Date: Tues 6 May 2008 11:36 am
Now for the biggie, the 7.62’s. The basic principle of headspacing hasn’t changed here but the practicalities have. Whereas before, on our rimmed .303” rifles we measured the GO NO-GO distance between the front face of the bolt and the rear face of the barrel, it’s all changed for the rimless 7.62mm NATO caliber rifles. Now we have to measure from the front face of the bolt to the cartridge seating at the neck. Well, that’s all pretty clear then ….., except that the neck is tapered so where EXACTLY on that neck do you take your GO, 1.628” and NO-GO 1.635 measurement from? Even if I told you it’d make no difference whatsoever because without the specialist measuring and more importantly, the calibration equipment, you’d still be none the wiser. The trouble with this is that you’ve got to take the word of the manufacturer of the gauge. And exactly where does HE take HIS measurement from but more importantly, WHO does he get them from. geting difficult isn't it?
Let me give you an example. My GO gauge gives you a close/GO reading of 1.628 but Bloggs & Co gauge may give you a GO reading of 1.575” for the same 7.62mm caliber. How can there be a difference of .053” between the two when they are identical? Well, it’s simple really. Our STANAG gauges are measured from one diameter around the neck while Bloggs & Co are taken from a different but larger diameter .053” further to the rear! That is really all I want to say about that.
The next obvious question for all you enthusiasts is where can I get a set of these gauges and the true answer is that I don’t know!

The fact remains that there are MANY gauges for all manner of 7.62mm rifles and machine guns ranging from the little bolt action L8’s right through to the L- whatever it is ferocious mini gun. And there are equally MANY for different lines of repair and functions, ranging from 1.622” to 1.648”.


That just about covers the 7.62mm versions. The question of calibrating your gauges is one that needs to be looked into by ‘some friends’ on both sides of the pond. I can see already that this is about to open up a whole new can of worms...... But just hang on in there....................
 

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Discussion Starter · #14 ·
Your extractor looks quite correct (or at least, it is the same as the one on my 2A1!)

The case gets pushed over to the left so that it will eject - the friction of the case base against the receiver wall helps fling the empty out of the action.

That being said, I too have found the 2A1 action much "stiffer" to operate than .303 SMLE's.
Thanks maxwell. My concern with the operation of the extractor was aroused when I tried to extract the un-fired case, and it extracted so tight. Confused me so, as these rifles were supposed to have the fastest actions of any bolt gun ever made. Interesting that this bolt gun ejects the brass straight forward of the rifle... I'm not sure if this is normal, or a condition cuased by the hard extraction I was experiencing.

There are some 12+ Nato specs for headspace on the 7.62.
Many firearms has a different specification.
Which rifle are the figures you quoted based ?

The actual headspace spec for the Ishapore 2A1 is :

The CHS for an Ishapore 2A1 is (They call it LOW) is GO 1.633" and HIGH or NO-GO is 1.642.

(information from the Indian Liasion Officer to Peter Laidler)

The other point in question is that the headspace measurement is taken at some random point on a 'slope', (where a rimmed cartridge is obviously much easier as the space between the back of the chamber and the front of the bolt head)

The fact that it would not close on your 1.638 (well between the Go & No Go dimension) tends to support that the theory of the dimension being taken from a different datum point

As Peter Laidler pointed out in one of his 'lectures' on headspacing a 7.62 if the Win 308 headspace is taken even a fraction of a millimetre in a different postion on the 'slope' than it will have a different measurement to one taken in the correct 7.62 position.

Also there is a 13 thou difference between Commercial and Mil spec chambers.




You just cannot use 308 gauges instead of 7.62 gauges.
I'll try and find PL's notes :

Anyone for 7.62mm CHS?
Posted By: Peter Laidler
Date: Tues 6 May 2008 11:36 am
Now for the biggie, the 7.62’s. The basic principle of headspacing hasn’t changed here but the practicalities have. Whereas before, on our rimmed .303” rifles we measured the GO NO-GO distance between the front face of the bolt and the rear face of the barrel, it’s all changed for the rimless 7.62mm NATO caliber rifles. Now we have to measure from the front face of the bolt to the cartridge seating at the neck. Well, that’s all pretty clear then ….., except that the neck is tapered so where EXACTLY on that neck do you take your GO, 1.628” and NO-GO 1.635 measurement from? Even if I told you it’d make no difference whatsoever because without the specialist measuring and more importantly, the calibration equipment, you’d still be none the wiser. The trouble with this is that you’ve got to take the word of the manufacturer of the gauge. And exactly where does HE take HIS measurement from but more importantly, WHO does he get them from. geting difficult isn't it?
Let me give you an example. My GO gauge gives you a close/GO reading of 1.628 but Bloggs & Co gauge may give you a GO reading of 1.575” for the same 7.62mm caliber. How can there be a difference of .053” between the two when they are identical? Well, it’s simple really. Our STANAG gauges are measured from one diameter around the neck while Bloggs & Co are taken from a different but larger diameter .053” further to the rear! That is really all I want to say about that.
The next obvious question for all you enthusiasts is where can I get a set of these gauges and the true answer is that I don’t know!

The fact remains that there are MANY gauges for all manner of 7.62mm rifles and machine guns ranging from the little bolt action L8’s right through to the L- whatever it is ferocious mini gun. And there are equally MANY for different lines of repair and functions, ranging from 1.622” to 1.648”.


That just about covers the 7.62mm versions. The question of calibrating your gauges is one that needs to be looked into by ‘some friends’ on both sides of the pond. I can see already that this is about to open up a whole new can of worms...... But just hang on in there....................
Alan - I had read both of the threads that this info had come from when doing my research. Except for getting the high and low from across the pond, it looks like us 2A1 owners are not much closer to feeling warm and fuzzy about our rifle specs. However, Brian Dick's name popped up on those threads as the armorer who has had to fix a number of these rifles so that they will safely headspace. I have been emailing him, and he said that without handling; measuring and firing my rifle, who could not confirm, but based on the 308 Field gauge I pictured, he thought my rifle "could" be in a safe margin of operation. He felt, again without first hand experience with my rifle, that my problem lies with reloading due to the fact that there are so many variables that could be out of sinc.
 

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Discussion Starter · #15 ·
The rifle closes on a GO and a NO GO, but not on a Field gauge:




Here is the primer (CCI #34) before:



And after firing:



More pics in the next post...
 

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Discussion Starter · #16 ·
I'm willing to bet the pockets are stretched on that one.

The base of the case swelled as expected: unfired




...and after firing and hard extraction:


The case in question (pictured above with the flattened primer) has another dimension that is un-nerving:


Many of the cases used in this loading fell within min/max trim dimensions and did not require trimming. This particular case could have been close to max, and after firing was stretched further by the hard extraction.

Here is a pic of the chamber, looks like it was cut so at the opening. Incidently, the numbers on the barrel match the receiver. In fact, all numbers match except for the mag (typical):

 

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Discussion Starter · #17 ·
Just a quick update; the 38gr's of IMR 4895 worked flawlessly; no hard extraction, except for what I reported on case friction when extracting an unfired round, and no flattened primers. Recoil was noticeably reduced, and quite comfortable. The rounds measured on average of 2450 fps with a 109fps extreme spread. Not the greatest, but I now have a base line to work from. Accuracy was all over the place at 50-yards, but I was mainly trying to keep the rounds over the chrony, was not necessarily working the target itself.

I still need to look at the action, as many videos on youtube indicate a smooth as silk action... a far cry from my "draggy" action.
 

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Hello,
I got the best accuracy with:

44gr of Vectan Tubal7000, 180 PRVI SP and OAL: 72.4mm

Groupings improved from 3 inches (same bullet and oal but with 38gr of Vectan Tubal 5000) at 50 meters to 1inch.
 

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Discussion Starter · #19 ·
Hello,
I got the best accuracy with:

44gr of Vectan Tubal7000, 180 PRVI SP and OAL: 72.4mm

Groupings improved from 3 inches (same bullet and oal but with 38gr of Vectan Tubal 5000) at 50 meters to 1inch.
Were you using a milspec case? My mistake first and foremost was using a commercial case in NATO chamber. I'm working at processing 200ea of 1964 dated Lake City Match cases for this rifle. I have 3 powders I would like work with, IMR 4064; 4895 and 8208 XBR. I'm pretty confident of finding a nice load using 4064 and 4895, but the 8208 XBR will be uncharted ground for me. being temp stable, and claiming to be accurate acrosss a wider spectrum than most powders, I feel I may be able to make a light load that is somewhat accurate and useable... I hope anyway, as I have no other use for the 2lbs of 8208 that I have on hand.

The `64 LC Match cases that I am working with came to me very dirty, and a little corroded. I had to tumble the ammo before I could even re-size & deprime. After celeaning the primer pockets, I am tossing the cases back into the tumbler for another 3-hour tour before I trim and reload them.

Hornady lists several loads for the M1A1 that I will use as a starting point. The data will allow me the starting data for 4064 and 4895. I will derive starting data for the 8208 from standard 308 Win. I will use the primers I have on hand, CCI #34, as they have been quite reliable across all of my rifles that I have reloaded for.
 

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Were you using a milspec case? My mistake first and foremost was using a commercial case in NATO chamber. I'm working at processing 200ea of 1964 dated Lake City Match cases for this rifle. I have 3 powders I would like work with, IMR 4064; 4895 and 8208 XBR. I'm pretty confident of finding a nice load using 4064 and 4895, but the 8208 XBR will be uncharted ground for me. being temp stable, and claiming to be accurate acrosss a wider spectrum than most powders, I feel I may be able to make a light load that is somewhat accurate and useable... I hope anyway, as I have no other use for the 2lbs of 8208 that I have on hand.

The `64 LC Match cases that I am working with came to me very dirty, and a little corroded. I had to tumble the ammo before I could even re-size & deprime. After celeaning the primer pockets, I am tossing the cases back into the tumbler for another 3-hour tour before I trim and reload them.

Hornady lists several loads for the M1A1 that I will use as a starting point. The data will allow me the starting data for 4064 and 4895. I will derive starting data for the 8208 from standard 308 Win. I will use the primers I have on hand, CCI #34, as they have been quite reliable across all of my rifles that I have reloaded for.
Hello,

I used comercial 308 cases...milspec cases are too thick, so have less capacity...44grs of tubal7000 need the comercial case capacity...and the 72.4mm OAL is the max the magazine allow to feed ok (at least in mine) and +/- the min before you compress the load.

I don´t know about american powders....but enfields like the slowest powders you can find...I spent years trying with faster powders without sucess.
 
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