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britrifles View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote britrifles Quote  Post ReplyReply Direct Link To This Post Posted: October 22 2020 at 7:44pm
Good news.  

Just continue to shoot and neck size the brass until you feel some resistance in closing the bolt.  When that happens, use your Hornady case length measuring tool to measure the length of the case (shoulder to case head) and adjust the full length die to shorten the case by .002 to .004 inches.  Check the sized case in the rifle chamber to be sure the bolt closes with no resistance, then continue again with neck sizing only.  You should get 30 or more reload cycles out of your brass.  You might have to separate the brass between the two rifles if the case headspace lengths are different by more than .005 or so. 

I suspect you will not see flattened primers with the neck sized cases with reasonable charge weights.  Load to .308 minimums.  You can go even lower than .308 minimums with H4895.  No reason to push these rifles to near max velocities.  

Are the PPU cases Identified as 7.62 NATO or as .308 Winchester?


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Frameman 1 View Drop Down
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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 22 2020 at 7:47pm
The PPU are 7.62 NATO 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote shjoe Quote  Post ReplyReply Direct Link To This Post Posted: October 23 2020 at 10:18am
most of my reloading is with fireformed cases segregated to each rifle. i then neck size only using cast bullets and moderate velocities @1700fps. i get good case life and accuracy with lower pressures when compared with loading jacketed rds. best regards, john
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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 23 2020 at 12:09pm
I’ve not tried cast bullets. Sounds interesting.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote britrifles Quote  Post ReplyReply Direct Link To This Post Posted: October 23 2020 at 4:35pm
For 100 yard (or less) shooting, you can’t beat cast bullets.  Very economical and virtually unlimited barrel life.  Cases last way longer too with low pressure loads.


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Post Options Post Options   Thanks (0) Thanks(0)   Quote shjoe Quote  Post ReplyReply Direct Link To This Post Posted: October 23 2020 at 10:20pm
cast bullet shooting is easier on the old girl, wallet and the shoulder. with a mold, a supply of lead and primers i dont have to scramble around looking for supplies every time an election draws near. my current 303 loading uses a medium hard cast lyman #314299 mold, 200gr round nose, flat based bullet on top of 2400 powder. lots of info on the web. http://castboolits.gunloads.com/showthread.php%3F13425-Cast-Bullet-Loads-for-Military-Rifles
with 1800fps and a 600yd sight setting 200yd accuracy is good with issue sights. makes a viable deer round. best regards, john
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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 24 2020 at 11:10am
When I try using my Hornady OAL length gauge with a 7.62 NATO modified case my bullets almost drop out of the case before contacting the rifling. Are the chambers on these mil-surp rifles typically have that much free bore? What 308 bullet Would be longer and allow enough bearing surface contact within the case neck?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: October 24 2020 at 11:20am
Frameman 1. 
I do not recommend seating the bullets in the case that far out. Unless you are a professional benchrest shooter with a Class 7 target rifle, seating the bullets to get them to touch the rifling is not conducive to safe chamber pressures. The OAL of the 7.62x51mm should be on average 2.800". Anything longer than that and you can develop higher than normal chamber pressure. The following photos show a 168grn BTHP seated to a depth of .400" with an OAL of just over 2.800". (Variants in actual bullet length due to inconsistencies in how much material is left after creating the tip from the manufacturer.) This is a handoad based off of an actual military match round that produces a chamber pressure less than 40,000 PSI.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: October 24 2020 at 11:58am
Seating the bullet in a case of a "Normal load" to allow about a 1/32" gap between  the bullet and initial contact with the rifling, pressure builds smoothly and steadily as the bullet takes the rifling. Pressure remains safe throughout the powder burning period. 

Seating the bullet deeper into the case allows more travel before the bullet takes the rifling.  This permits the bullet to get a good running start. Powder gases quickly have more room in which to expand without resistance and the pressures never reaches the "Normal" levels.

When the bullet is seated to touch the rifling, it does not move when pressure is low and not having a good run at the rifling, an excessive amount of pressure is needed to force the bullet into the rifling. Rapidly expanding gases now have less room than it should have at this time in the powder burn period. The pressure rise is very rapid and excessive resulting in dangerous conditions...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: October 24 2020 at 12:23pm
The handload pictured is a 180grn Norma Vulkan hunting bullet that I use in my No4Mk1/2 converted to fire 7.62x51mm NATO.
 The case is Norma and the powder is 39.0grns of Norma 202. The primer is Federal Gold Match GM215M. 
The OAL is 2.700".
The published Piezo chamber pressure for this particular load is 38,400 PSI.  That is a CUP of 30,647 and well under the working 45,000 CUP pressure of the 303B round.
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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 24 2020 at 12:54pm
I had intended to reduce the “jump “ distance by .040” from the rifling. Would that be acceptable with any bullet length?
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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 24 2020 at 1:00pm
I wasn’t able to calculate the ogive to rifling distance because of the ,too short bullet. I want to keep the contact patch equal to the diameter of the bullet itself. I’m trying to learn and experiment without damaging either myself or my rifle.😎
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: October 24 2020 at 1:15pm
I would, in this instance, stick to published seating depth and OAL. The "bullet jump", should be kept to as close to reloading manual specifications as possible to keep pressure down, extending the life of the rifle.
To answer your question however.  .035" -.040" is an acceptable distance from the bullet ogive to the rifling .
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: October 24 2020 at 1:30pm
Originally posted by Frameman 1 Frameman 1 wrote:

I wasn’t able to calculate the ogive to rifling distance because of the ,too short bullet. I want to keep the contact patch equal to the diameter of the bullet itself. I’m trying to learn and experiment without damaging either myself or my rifle.😎
I would recommend to set your C.O.L. at  2.750" - 2.800" for the Hornady 165grn SST. Why calculate when the calculations have been done for you by Hornady and their reloading data on page 417 of the 9th Edition?
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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 24 2020 at 1:37pm
Of course you are correct. I just can’t resist tinkering and in the process learning. I’m just fascinated with older military rifles and the reasons the engineers designed them as they did.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: October 24 2020 at 2:05pm
Here is where I impart my knowledge of tinkering when you should not.
 I had a very nice sporterized Lee Enfield No4Mk1. I was calculating the necessary charge weight of IMR3031 to use in conjunction with a .3105" 200grn D166 Lapua bullet with a seated C.O.L. of 3.000".  I overcharged the cases by 4 grains. The bolt was bent as was the reciever after firing. It cost me a rifle. Fortunately, that is all it cost me. The cartridge was nowhere to be found when I was finally able to get the bolt freed. 
The Ishapore 2A/2A1 rifles are, in my opinion,  a very poor choice of rifle to be produced to chamber the 7.62x51mm NATO cartridge and as such should be reloaded for with caution using any published data where minimum charge weight and a published AOL is set as standard. I use the 2A1 barrel indexed to a No4Mk1 reciever and that, is my saving grace, being that the No4 reciever is stronger and able to withstand the rare but occasional over than normal pressure my handloads may produce.
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