Load data for IMI 7.62 razorcore 168gr semi-auto match?

[alchrisr]

I have searched around and have not found any data listed for this round. It works really good in my .308 gas gun (sun devil(?) upper and lower with Fulton bcg and Criterion 20" stainless hbar). I currently shoot a hand load with 175 Nosler custom comps over 44gr of Varget (same as my bolt gun load), but it is hard on brass. The IMI crono's close to that load (min 2642, max2674,avg 2651, sd 12.3). I ran a test group last week using 168grSMK over 4064 starting at 40gr up to 43.5 and even a group with 44gr of Varget in Winchester brass. Averages ran from 2368 to 2580 which I thought a bit to slow and I started seeing ejector swipes at 43gr. My Varget 44gr/175 load produces AVG 2613 ES 20.9, SD 7.61 using these same cases. I have seen the AVG well over 2700 with other head stamps but the SD gets a good bit higher. I have good case capacity data on all my brass but have not tested the IMI brass as yet to see where it compares. The only bullet puller I have is an impact hammer type so I cant get an accurate look at the powder in the IMI loads. Just wondering if anyone has duplicated IMI semi-auto match load?

Thanks,

CR

 

[Desert Ranger Tycho]

Following

 

[308pirate]

There is no way of duplicating the recipe of a factory load unless you have hard evidence of which primers and which powder they used

Most of the times you can't even do it if you know which powder was used since many powders used by OEMs are formulations not available to reloaders.

Just looking at the powder won't tell you anything.

 

[Baddog 0302]

Don't know why you say you can't get an accurate look at the powder in the IMI loads ? The round is in a closed container, you hit the puller till the bullet comes out with the powder, desperate the bullet from the powder. The other way is to destroy the bullet by using vice grips instead of a collet type puller and your press. BUT either way all you will learn is the amount of powder used. Because as stated above, the OME's use a special blend we can't buy.
If you want to duplicate the MV you are going to have to go to slower powders , but your accuracy may not be what you want.

 

[Xcount]

the easiest way to loosen the bullet is to put it in your press and push it in about .060" that will break any sealant, doubt there is any on match rounds, or if there is a heavy crimp. Then use your kinetic bullet puller. I agree with the others, its doubtful you will be able to identify the exact powder or even get it on the commercial market. just use Varget.

 

[Howland]

Knowing both how much powder and velocity gives you an understanding of the burn rate and narrows down the list to similar powders. What they actually use might not be knowable or available.

I picked up a bulk lot of IMI Match 7.62 brass. I got a spread of just over .295 grams and SD of 0.045 grams (0.7 grains). I did not measure case capacity.

 

[alchrisr]

Appreciate the replies guys. I even sent an email to IMI to see if I could get any response, nothing. I do understand that just pulling a cartridge apart will not reveal some mystical magic knowledge, but you have to start somewhere when trying to reproduce a load and that somewhere is breaking down a known cartridge to get an insight on type and weight of the powder. That at least gives some sort of starting point to develop the load. As for the kinetic hammer to break it down, I have never been able to capture all the powder in the hammer. There is a foam nugget to cushion the bullet and powder always gets stuck down there. Mine has all sorts of remnants in it. I suppose I could clean it thoroughly and use it and that might get pretty close to the powder weight. Whenever I get some time I will break down a cartridge and start to build the load.

 

[Doom]

Your 2580ish is right in line for 4064 and 43.5gr in a 20 inch barrel. You may be able to push the load up to 44.5, depending.

If you are really seeking velocity, try 2000MR, but I would highly recommend an adjustable gas block.

 

[Greg Langelius *]

My Match load for the 7.62x51/168 has been 43.5gr IMR-4064, and it prints identical to FGMM (168).

Owing to the current powder shortages, I am on a project redeveloping my 150gr and 168gr loads with W748 and W760. W748 was one of the original factory propellants from Winchester in the mid-1960's.

Since my loads will not be intended for military type usage, I will also be testing Speer 150gr and 168gr Gold Dot Rifle Projectiles.

I seldom/never shoot loads with bullets heavier than 168gr. Not up to the recoil in a repetitive range scenario, and I also live at 4350ft ASL, which tends to have a beneficial effect on effective BC.

While my background was once heavily into LR shooting, these days it centers a bit more around just how far I can carry that carcass back to the car, and/or how far the trek is to service targets.

Greg

 

[Old Corps 8541]

There is no way of duplicating the recipe of a factory load unless you have hard evidence of which primers and which powder they used

Most of the times you can't even do it if you know which powder was used since many powders used by OEMs are formulations not available to reloaders.

Just looking at the powder won't tell you anything.

What this gentleman said, the three variables are primers , powder and bullets , and you can't get any of them , because all 3 are made in house , and the IDF is probably is using their facilities to stock pile munitions for their next war.
Lots of gas gun data under the 308 AR only section

 

[Doom]

Owing to the current powder shortages, I am on a project redeveloping my 150gr and 168gr loads with W748 and W760. W748 was one of the original factory propellants from Winchester in the mid-1960's.

You probably won't get 760 to work very well. In a 26" barrel only about 85% of the powders burns out and the the velocities are low with a full case.