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Frameman 1 View Drop Down
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    Posted: October 14 2020 at 4:09am
I fired these rounds yesterday. I used new Hornady 308 cases with CCI 200 primers , Hornady 165 gr, SST bullets with 42 gr. Of IMR 4895 powder. I thought this load would be fine but the signs say otherwise.
Any thoughts? 
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Goosic View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 5:10am
According to Hodgdon and using Fed 210M primers, they indicate a starting load of IMR 4895 at 40.7grns. The psi is only 49,200 with a velocity of 2584. 
It gives a maximum compressed load of 45.5grns, a psi of 58,800 and a velocity of 2745.
You might be experiencing an issue of not enough powder. The line around the fired case is well above where a case separation occurs and may have something to do with the way the chamber was reamed.
What rifle are you experiencing this issue with?
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The Armourer View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote The Armourer Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 6:19am
As this is posted in the Ishapore section of the forum I'll assume that that is what we are talking about.

Remember that these rifles were only proof tested based on the 144 gr NATO bullet, and even then the Proof testing was fudged to get them to pass.

I am no expert on pressures but listen to those with much more experience than I

It is not ideal to use heavier weight bullets.

Heavier bullets accelerate slower than lighter bullets. Slower bullets means less space behind them which means higher pressure, which means faster powder burn which means even more pressure.

There is s discussion about the 2A / 2A1's on another forum where Brian d**k* suggests that nothing other than NATO 144gr should be used - he had one to repair where someone decided to load up to M118 LR specs with a 175gr bullet and wondered why the bolt disintegrated.

*Brian (BDL Ltd) is possibly one of the most experienced armourers and repairers of LE's in the USA.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote The Armourer Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 6:35am
Originally posted by Goosic Goosic wrote:

According to Hodgdon and using Fed 210M primers, they indicate a starting load of IMR 4895 at 40.7grns. The psi is only 49,200 with a velocity of 2584. 
It gives a maximum compressed load of 45.5grns, a psi of 58,800 and a velocity of 2745.
You might be experiencing an issue of not enough powder. The line around the fired case is well above where a case separation occurs and may have something to do with the way the chamber was reamed.
What rifle are you experiencing this issue with?

As I have said - I am no expert on loading and looking to learn.

If the OP is using 42gr  and the 'manuals' say a minimum load is 40.7gr (is that for 308 ?) why would the OP's 42 gr be 'an issue of not enough powder' ?

Would the bullet being 15% heavier than the rifle was designed for not also cause pressure problems ?
Would the fact that 7.62 cases are thicker and have less volume than 308 cases not cause a rise in pressures as well ?


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Post Options Post Options   Thanks (0) Thanks(0)   Quote Honkytonk Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 6:36am
A while ago I was wondering asking a question on minimum/maximum loads, but didn't as I thought it might be too obvious. We all know the potential dangers of loading to maximum or over with these older rifles. Actually, any rifle for that matter. Other than the bullet stopping half way down the barrel, what are other potential dangers of loading below recommended powder charges? Thanks!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Frameman 1 Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 7:18am
the rifle used was an Ishapore 2A1. Cut down by Gibbs most likely into a tanker carbine.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 7:23am
Originally posted by The Armourer The Armourer wrote:

Originally posted by Goosic Goosic wrote:

According to Hodgdon and using Fed 210M primers, they indicate a starting load of IMR 4895 at 40.7grns. The psi is only 49,200 with a velocity of 2584. 
It gives a maximum compressed load of 45.5grns, a psi of 58,800 and a velocity of 2745.
You might be experiencing an issue of not enough powder. The line around the fired case is well above where a case separation occurs and may have something to do with the way the chamber was reamed.
What rifle are you experiencing this issue with?

As I have said - I am no expert on loading and looking to learn.

If the OP is using 42gr  and the 'manuals' say a minimum load is 40.7gr (is that for 308 ?) why would the OP's 42 gr be 'an issue of not enough powder' ?

Would the bullet being 15% heavier than the rifle was designed for not also cause pressure problems ?
Would the fact that 7.62 cases are thicker and have less volume than 308 cases not cause a rise in pressures as well ?


I misread his original post The Armourer . My apologies to you and yours.

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The Armourer View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote The Armourer Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 8:16am
Originally posted by Goosic Goosic wrote:

Originally posted by The Armourer The Armourer wrote:

Originally posted by Goosic Goosic wrote:

According to Hodgdon and using Fed 210M primers, they indicate a starting load of IMR 4895 at 40.7grns. The psi is only 49,200 with a velocity of 2584. 
It gives a maximum compressed load of 45.5grns, a psi of 58,800 and a velocity of 2745.
You might be experiencing an issue of not enough powder. The line around the fired case is well above where a case separation occurs and may have something to do with the way the chamber was reamed.
What rifle are you experiencing this issue with?

As I have said - I am no expert on loading and looking to learn.

If the OP is using 42gr  and the 'manuals' say a minimum load is 40.7gr (is that for 308 ?) why would the OP's 42 gr be 'an issue of not enough powder' ?

Would the bullet being 15% heavier than the rifle was designed for not also cause pressure problems ?
Would the fact that 7.62 cases are thicker and have less volume than 308 cases not cause a rise in pressures as well ?


I misread his original post The Armourer . My apologies to you and yours.



No problem, I thought I was just misunderstanding it.

I'm trying to increase my re-loading knowledge - I only reload for my 303's using the wack-a-mole system.
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Post Options Post Options   Thanks (1) Thanks(1)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 8:49am
Originally posted by The Armourer The Armourer wrote:


Remember that these rifles were only proof tested based on the 144 gr NATO bullet, and even then the Proof testing was fudged to get them to pass.

There is s discussion about the 2A / 2A1's on another forum where Brian d**k* suggests that nothing other than NATO 144gr should be used - he had one to repair where someone decided to load up to M118 LR specs with a 175gr bullet and wondered why the bolt disintegrated.

*Brian (BDL Ltd) is possibly one of the most experienced armourers and repairers of LE's in the USA.
 
It is interesting that you brought up the M118LR.
I have been using the updated M852 special ball ammunition to the original M118. It is handloads consisting of the 168grn BTHP, 41.0grns of IMR4064, and GM215M primers. I also use for the really long range stuff, the MK316 MOD O special ball. That consists of a 175gr BTHP,  41.7grns of IMR4064 and GM215M primers as well. Both rounds have been extensively used in my No4Mk1/2 with the 2A1barrel.  No noticable pressure issues,no blown primers,no case separation, and no issue with extraction of a spent round. I have witnessed on a few occasions, a primer that has backed itself out of the pocket from an undercharged round. That in conjunction with a light firing pin strike. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Frameman 1 Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 9:39am
This is the load data I was using from Hornady 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 9:54am
You are right on the cusp of a max charge. Hornady has a starting weight of 35.0grns of IMR4895. Always start with the minimum and work your way up.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Frameman 1 Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 10:44am
you are correct. I jumped ahead a bit too far
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Zed Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 11:39am
As a side note. The rifle bolt mentioned by Armourer; that was discussed on another forum came from an L42A1. These No4 type are stronger bodies than the SMLE type. Yet they can still fail if you load heavy bullets with hot loads. 
I think that keeping the bullet velocity similar to that of the standard .303 is probably adviseable if using bullets of a similar weight.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote britrifles Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 5:49pm
From the Hodgdon web site:



H4895 powder performs exceptionally well with reduced loads (less than published minimums).   Some powders will not ignite and burn consistently with loads less than minimum, not a problem with H4895.  

My approach has been to load the .308/7.62 converted No. 4 rifles to within .303 British pressures, can’t go wrong with this.  

The No. 4 action was never designed to 7.62 NATO or .308 Winchester.  It was designed to use the .303 British Mk 7 cartridge.  If you want your rifles to last for 30,000 rounds, keep loads well below the .303 British maximum average pressure of 45.000 CUP (preferably below 40,000 CUP).  

The thrust loads on the bolt are a function of the chamber pressure and area at the rear of the chamber, the .308 is slightly larger in diameter than the .303 at the base of the cartridge.  


 








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Post Options Post Options   Thanks (0) Thanks(0)   Quote Frameman 1 Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 6:05pm
Going forward, my loads will be towards the lower end of range provided by the manufacturer of whatever components I’m using.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: October 14 2020 at 8:34pm
Just a suggestion.  Start with 36.0grns of IMR4895,  stay with the 165grn SST bullets as well as the CCI 200 primers. Your velocity will not exceed 2200 fps, the pressure limits will never be reached, and barrel wear will be reduced greatly. 
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