Replacing fmj with soft points in 7.62 surplus

Grizzlypeg

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Just for fun I popped the fmj bullet out of a FNM Portugese 7.62x51 cartridge. Weighed the powder (44.5 gr) and bullet (147.5 gr) for curiousity's sake. Then I put the powder back in the case and replaced the bullet with a 150 gr soft point. Any reason why this would be a danger to fire? I'm curious how accurate these might turn out to be. I have a couple hundred rounds and its sure easy to swap bullets in them, if they would be a good hunting round.
 
This is called making "Mexican match". I have done a lot of experimenting with doing this with 7.62 x 51.

Any soft point bullet will be more accurate than the military FMJ. Joyce Hornady once told me that their accptance standard for their FMJ was a group almost twice as big as for their 150 gr Spitzer soft point.

You mentioned accuracy. My testing suggests the following:

Pull the bullets and collect the powder.
Champfer the case mouths.
Run all the cases into a conventional neck sizing die with the decapping pin removed. (not a Lee collet.) This will give maximum neck tension and improve accuracy.
Add powder back and seat bullets.

Powder charges:
Reduce powder charge 1 grain to maintain the same pressure, which is usually in the order of 53,000 to 58,000 psi.

To improve accuracy, reduce the powder charge another grain. This ammo is great for plinking out to 600 yards.

To make real good target ammo, use a 155 gr match bullet and reduce the power charge 2 grains.

Once upon a time I bought a lot of 7.62 surplus for only $35/1000, so did a lot of work figuring out what to do with it. My results were all tested and approved for sale by the Explosives Branch.
 
Thanks Ganderite. Its too bad you can't get it at the prices you used to. I was just figuring that if adding a 23 cent bullet was all I had to do to make a decent hunting round or more accurate target round, its worth playing with. It surprised me how easy it was to pull a bullet.
 
Tested out 10 rounds in my M14 of the cartridges with swapped out fmj for soft points. Function was 100%. Accuracy was mediocre. At 100 yards they were no better and no worse than the original FNM fmjs. Certainly good enough for a deer at 100 yards. But, I get much better groups with Federal 308's than these. I could experiment with lightening the loads, resizing and bullet seating depth. I did seat the bullet to the cannellure, which resulted in a slightly shorter OAL than the original fmj's.
 
I've heard a few guys find that heavier bullets often get better accuracy than the 150's. If you went to 165's you might be better off. Incidentally, I shoot exactly the same amount of the same powder in both my 150 and 165gr loadings and looking at my half dozen reloading manuals, there is significant overlap in powder weights between 150's and 165's noted there as well - you probably won't have to mess with any powder changes to load 165's - just stick them right in there. On another note - I have found VERY LITTLE velocity difference between 150's and 165's with the same powder. I shoot 45gr of IMR 4895 - I get 2750 fps with 165's and 2780 with 150's, a measly 30 fps. So nataurally I prefer the 165's.
 
Good point Northman. That would be something to try. I need some more bullets anyway. Doesn't take long to go through a 100 when you like to shoot.
 
Don't forget to neck size the cases, without a decapper pin installed. The increased neck tension is important to the results.

An M14 is not the best choice of rifles to compare accuracy results, but it is important to test, if you are going to hunt with it.

I have had really good accuracy with the Hornady 165 interlocks. But in my target rifle, both the 150 and the 165 shot under an inch.
 
How critical is the overall length when seating the bullet? I seated them until the cannelure was effective. I figured the rapid chambering action of the M14 dictates a need for a firmly secure bullet.
 
I'm running 45gr of IMR4895 in my bolt gun with 150gr bullets. The max load from two sources is 47.3gr with a 150 gr bullet. 45 grains seems to shoot quite well in my Tikka so I'm sticking with it. I'm too chicken to try reloads in my M14 yet. Worried about the whole slamfire issue. I still have enough milsurp to keep me happy and it was likely intended for use in m14's.
 
I've cranked out a few hundred reloads from my M14 without any problems. Just make dang sure you seat the primers so they below the face of the brass and you should be good to go.
 
This is called making "Mexican match". I have done a lot of experimenting with doing this with 7.62 x 51.

Any soft point bullet will be more accurate than the military FMJ. Joyce Hornady once told me that their accptance standard for their FMJ was a group almost twice as big as for their 150 gr Spitzer soft point.

You mentioned accuracy. My testing suggests the following:

Pull the bullets and collect the powder.
Champfer the case mouths.
Run all the cases into a conventional neck sizing die with the decapping pin removed. (not a Lee collet.) This will give maximum neck tension and improve accuracy.
Add powder back and seat bullets.

Powder charges:
Reduce powder charge 1 grain to maintain the same pressure, which is usually in the order of 53,000 to 58,000 psi.

To improve accuracy, reduce the powder charge another grain. This ammo is great for plinking out to 600 yards.

To make real good target ammo, use a 155 gr match bullet and reduce the power charge 2 grains.

Once upon a time I bought a lot of 7.62 surplus for only $35/1000, so did a lot of work figuring out what to do with it. My results were all tested and approved for sale by the Explosives Branch.

Ganderite,
I'm going to ask a real reloading-newbie question here regarding your very detailed and specific instructions. You say "Run all the cases into a conventional neck sizing die with the decapping pin removed. (not a Lee collet.)" I'm curious as to why the Lee Collet (which I understand to be a neck-size-only die - maybe I'm mistaken) is an incorrect choice for this task.

Hoping to learn something to add to my notebook. :D

Thanks
FB
 
Quote: "I'm running 45gr of IMR4895 in my bolt gun with 150gr bullets." This is around max in most rifles - with commercial brass. It is too hot in a military case.

Quote: "I'm curious as to why the Lee Collet (which I understand to be a neck-size-only die - maybe I'm mistaken) is an incorrect choice for this task."

There are many variables in loading ammo. Neck tension is one of them. When you pull military bullets so you can substitute a match or hunting bullet, the neck is not as tight as it once was. The obvious solution is to neck size.

The ammo we are discussing is primed, so there is no point in decapping it. If we did decap it we would have trouble repriming because the pocket is crimped. And the brass of a lot of surplus ammo is Berdan - it wont decap anyway.

The Lee Collet die squeezes the case onto a combination manderal/decapping rod - so it won't work in this applciation. The best die is an ordinary neck sizing die since it does not need lubing. Second best is to use a full length die and run the neck about 3/4 of the way into the die.

I suggest the decapping rod be removed, not just backed out so as to not decap. The rod has a neck button that opens the neck on the way out.

When involved in a project to make many thousands of rounds of Mexican Match 308 using the Sierra 155 bullet, we ran tests and found that sizing the neck without opening it up increased neck tension to the max and cut group size dramatically.
 
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