Today at the Bench.....

[Harter]

Started ..... restarted a milsurp . It's a 7.7×58 Arisaka.

Cast bullets ahead.
Casual observations about the cartridge itself . Imagine an 8×57 necked to .310 with a neck only .320 long and a 308 shoulder that loads to almost 06' length . Makes it a lot closer to 06' than 308 . The twist is about 1-9.5" so hurling Volkswagens is possible, if not practical .

The other bug is that this one oversized a fair bit and of course has the round top and bottom Metford rifling, it looks like this ~ but round with 4 lands and grooves . It is .316×.305 . That's cool I have tools and bullets for that . It has a need for .318 to fill the throat . The formed from 270 is going to have to be reamed a .320 makes me force the bolt . It may be a lost cause .
The 8×57 brass is a little better for fit but also short and the shoulder is in the wrong place , too far down .

All minor inconveniences really. The sizing may force me to buy more new dies .

[JeffreyDeGraff]

Started ..... restarted a milsurp . It's a 7.7×58 Arisaka.

Cast bullets ahead.
Casual observations about the cartridge itself . Imagine an 8×57 necked to .310 with a neck only .320 long and a 308 shoulder that loads to almost 06' length . Makes it a lot closer to 06' than 308 . The twist is about 1-9.5" so hurling Volkswagens is possible, if not practical .

The other bug is that this one oversized a fair bit and of course has the round top and bottom Metford rifling, it looks like this ~ but round with 4 lands and grooves . It is .316×.305 . That's cool I have tools and bullets for that . It has a need for .318 to fill the throat . The formed from 270 is going to have to be reamed a .320 makes me force the bolt . It may be a lost cause .
The 8×57 brass is a little better for fit but also short and the shoulder is in the wrong place , too far down .

All minor inconveniences really. The sizing may force me to buy more new dies .

I always love when you post here, your stuff is very interesting and I love reading it. Is your arisaka stock or sporterized?


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[Harter]

Barrel and stock are cut . It's modified with a magazine release , bent bolt , and recoil pad . If the type 38 sights are an example of the issue sights the Williams front ramp and rear set are a huge improvement.

I don't know that I have especially unique examples but rather examples that just need a little more than average attention to shoot well .

I like to share the trip , it often helps me sort things out , those "oh yeah I see the problem now that I've written it down" moments . It might save someone else a trip down a blind alley.

[JeffreyDeGraff]

Barrel and stock are cut . It's modified with a magazine release , bent bolt , and recoil pad . If the type 38 sights are an example of the issue sights the Williams front ramp and rear set are a huge improvement.

I don't know that I have especially unique examples but rather examples that just need a little more than average attention to shoot well .

I like to share the trip , it often helps me sort things out , those "oh yeah I see the problem now that I've written it down" moments . It might save someone else a trip down a blind alley.

Sounds like my kinda rifle.


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[Harter]

Interesting outcome.
I got some 45-70 brass from a guy someplace with some other brass . The head separation was just age and brass fatigue . I doubt the loads were much over 18kpsi . A 530 gr RCBS 45-500 FP from a 1895G at 935-945 and 1045 fps . There were 2 loads of 5 ea but I had gremlins in the man cave that mixed them together. The 940s I think were 35 gr of 4831 , Ken Waters published, and the 1040s were 9 gr of Unique. The Rem-UMC brass is seen sans rim and head .
The interesting part isn't the fabulous group , I blame the operator and shooting both open through an FP 95 that shows the front hood well inside rear halo . What is interesting is it looks like the rifling lands cut clean where they were tipped out .
8821.jpeg

[JeffreyDeGraff]

Interesting outcome.
I got some 45-70 brass from a guy someplace with some other brass . The head separation was just age and brass fatigue . I doubt the loads were much over 18kpsi . A 530 gr RCBS 45-500 FP from a 1895G at 935-945 and 1045 fps . There were 2 loads of 5 ea but I had gremlins in the man cave that mixed them together. The 940s I think were 35 gr of 4831 , Ken Waters published, and the 1040s were 9 gr of Unique. The Rem-UMC brass is seen sans rim and head .
The interesting part isn't the fabulous group , I blame the operator and shooting both open through an FP 95 that shows the front hood well inside rear halo . What is interesting is it looks like the rifling lands cut clean where they were tipped out .
8821.jpeg

That is really cool!


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[Harter]

I ran Strelok for the 530s at 1100 fps MV . If I can get it down to a good solid repeatable 2.5" at 100 I'll have it made . It looks like it'll come together if I can get another 150 fps out of the H4831 which is a BP like full case at 35.5 gr in PPU brass . 1100 fps MV takes 1000ftlb out to 300 yd and has about flight from 150 as the FTX and 1/3 of the recoil .

[Harter]

I got out a box of new brass for Dad's 25-06' it's just one box of 20 but it's better than the formed and previous collection of 7-8 WW , 5 Super X , 8 FA 41 and a dozen or so other formed 06' and 270s . This is probably the only time I've weighed RP brass and only had 2 gr of difference from light to heavy . 192.4-196.6 , I'll take it for a box of new 1972 brass . Maybe it'll clean up the dispersion per 5 round load work up in matchingish brass . I know what the rifle would do but that matching brass has wandered off. I suppose it's possible that the barrel needs to be set back and recahambered it can't over 1000-1500 rounds through it but it is a little hole in a big case fed canon powder for ......holy crap it's 51 in just a few weeks....... The original Hogdon 4831 was surplus from the WWII 20mm canon contracts .

KIMG0536~2.JPG

The rifle is a 700BDL Varmint Master .790 at the muzzle bull barrel so there's plenty of meat to set it back a half inch if needed.

[JeffreyDeGraff]

Sounds like a cool old rifle. Ive had a few barrels set back through the years. Really helps those eroded throats. Most times I just rebarrel though.

Ive only weighed brass one time. When I was comparing case capacity between 9.3x62 and 375 Whelen improved. They were very similar. Other than that I just roll with matching headstamp brass and call it good.


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[Harter]

I did a batch circa 98-00' RP 100 rounds one lot of 165s in 06' and had the same dispersion as war production LC from very likely 3-4 lots on 180 pieces from 189-208 gr . That was very disappointing on the RP , it did explain why my buddies 700BDL lefty "suddenly losing" its MOA accuracy.