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william iorg
06-02-2006, 06:19 PM
I am wondering if anyone has experience with low velocity, 1,000 fps and less, 7.62 X 39 handloads.
I have begun to work with the owner of an AK-47 in developing some low velocity hunting loads for predator and varmint control. This interesting rifle has an 18.5” barrel and is in “bullpup” configuration.
I have been shooting the Ed Harris designed Lee 155 grain gas check bullet both with and without gas check, using Javelina 50-50 Alox lubricant, Winchester brass and primers.
One load has shown itself to be a winner from the beginning; the Ed Harris inspired (I think) load of 5.0 grains of Alliant Bullseye. This load is remarkably accurate at 25 yards with five shot groups that will beat 1.0”. Considering the sighting system, a red dot laser, this seems to be very acceptable accuracy. Without gas check this load is averaging 1,092 fps with extreme spreads and standard deviations that run in the single digits.
When the bullet is gas checked the load averages 1,098 fps but the extreme spreads begin to climb, averaging 11 fps with the standard deviation running 7 fps.
With both of these loads the loudest noise is the action attempting to cycle and returning to battery.

I have loaded a few 174 grain FMJBT target bullets and the owner of the rifle has purchased some low velocity 220 grain JHPBT ammunition that was loaded in salvaged military cases. The powder for these loads appears to be Hodgdon 4227; the charge weight is 12.5 grains. My 174 grain FMJBT bullets and the commercial 220 grain loads, both over the 12.5 grain Hodgdon 4227 load, display the same good accuracy with velocity unfortunately running a little faster than desired.

I am specifically looking for anyone with experience using 165 grain .308 diameter bullets in the 7.62 X 39 at 1,000 fps.

I have attached a picture of the Winchester case, Lee 155 grain cast bullet, 174 grain FMJBT, 220 grain JHPBT and a military Berdan primed case.
As you can see, when the bullets are seated to a COAL of 2.186” there is not a lot of room left for powder.

This interesting little project has temporarily stopped my playing with the .25-35 and .25-35AI.

mercmarine
06-02-2006, 07:13 PM
- I don't reload...yet.

- However...I do have a considerable amount of experience working with the .308Win-Cartridge at subsonic-velocities. Every so often I work with Designated-Marksman-LE-Teams that deploy this round through a suppressed-tube on a Remington-M700-Series-Rifle. I have shot some of these rounds through my Steyr-Scout-Carbine at ranges from 50-100M and they are quite a delight to shoot. That .30-Cal projectile flys downrange like a speeding football...and they make a motivating "THUNK-WHOP" noise when they impact the steel-plates. I have a CZ-527 in 7.62X39...some "slow-movers" for that would be a joy to shoot.

- I bet that would be a DANDY Predator/Varmint control-round at close to intermediate game-range.

mercmarine
06-02-2006, 07:32 PM
- I bet that would be a DANDY Predator/Varmint control-round at close to intermediate game-range.

...Don't let the 7MM-REM/300WIN-MAG-Guys know....But - you could kill a DEER with this round-too :D .

ribbonstone
06-02-2006, 08:22 PM
You've been working harder at this that i did. Getting non-cycling low vel. rounds that shoot well wasn't a problem...it's a good cast bullet gun, using most of the light molds designed for .32revolvers and the older Lyman molds (that usually drop out nearer to .311" than .308") to good effect.

They don't cycle..figured i'd put the Yugo's gas cut off to good effect and get rid of the action slap (which also tends to occcasionaly crush an almost cycled case).

Never did get very good accuracy with .308" bullets in that rifle, so I've little experience with them. Pulled .303brit FMJ's did well, but again no functioning without a good bit of noise (transonic).

------
Going the other direction, loaded some 85gr. .32revolver JHP's to 2900fps (there seemed to be room to go higher, but didn't push things) for a friend with a garbage raiding racoon problem. Penetration severly limited...expansion/fragmention impressive.

valter
06-02-2006, 11:39 PM
There is a gentleman from Calgary that had developed some subsonic loads for varmint control. Here is the link:
http://members.shaw.ca/cronhelm/DevelopSubsonic.html

Hope it works.
Good luck.

william iorg
06-03-2006, 06:26 AM
I have considerable experience shooting the larger cases at low velocity. This smaller case presents some small but different challenges.
With the unsuppressed bolt or single shot rifles the loudest noise seems to be the primer.
Paco Kelly on Leverguns has shot quite a bit of heavy bullet low velocity ammunition at coyotes. C. E. Harris who has posted on Beartooth some seems to be one of the most active experimentors. Forum member Greg Mushial at GMDR.com is also a big fan of low velocity shooting and has quite a bit of load data on his web site. He is updating it now and has two slightly different pages up under the lever action rifle.
I have a Model 94 Trapper with a forward mount scope and a friend has a Savage 110 Scout rifle. I like the principle.
My father shoots two .300 Whispers and I have a 24" .32 H&R Magnum - a rimmed Whisper if you will.
You mention the exact draw of these cartridges. A large bullet making a good thump with no recoil. You can feel the trigger slide across the sear and break. At the snap if you concentrate you can see the bullet hole appear!

It appears very little work on the recoil spring will have the action working semi-auto with these low velocity loads.

EDIT]Ribbonstone, I'll look at the light bullet high velocity load later jn the summer.

Thanks for the link, it looks interesting.

ribbonstone
06-03-2006, 01:55 PM
Can start with the published loads for the 123-125gr. bullets (Hornady lists loads) with those little 85 or 90gr. JHP's and nudge it up a bit until you get reliable cycling. No real reason to push them past that point, are too stumpy to make a long range load...but at short range they can be truely impressive.

Most of my low vel. lead bullet shooting has been geared to (1) plain based bulelts of 110-120gr. and (2) non-cyling loads...use the rifle as a stright pull manual repeater. I want a vel. of under 800fps for the quiet...but even at those low speeds, these loads are small game killers.

william iorg
06-03-2006, 02:13 PM
I will take a closer look at this. We are big .32 H&R Magnum fans and have a good store of both jacketed and cast bullets that would be useful here.

ironhead7544
06-04-2006, 12:38 AM
Check Loadswap for some subsonic loads.

william iorg
06-04-2006, 07:20 AM
I have looked at this load - using SR7625. I have a little of this powder and will compare it to Accurate No. 2 with the same weight bullets.
I am glad you brought this one up as his COAL is a little shorter than mine. I am assuming he is using the flat base spitzer. With 100% load density I believe 7625 may be a better selection than A.A. No. 2 in the bottle neck case.