762x39 to 303 british MEXICAN MATCH AMMO
- Thread starter lone ranger
- Start date
Anyone have any concerns of flash over on the powder?
Any thoughts on taking 20rds of 7.63x39 and bumping up the powder a bit?
7.62x39 has a narrow burn rate powder band, so looking at max loads of powder in 7.62x39 you are around 28-30gr, those same powders min loads in 303 Brit 125gr are 41-42, 25gr seems really light here.
Would it not be better to use the powder at around 15rds of 303 Brit from 20rds of 7.62x39? That would be around 40gr, but this would be a work up of course.
The 7.62x54R is another weird one, for the same powders between the two rounds, 150gr, the difference based on published recipes is 5-9gr from minimum load to minimum load with the 7.62x54R having more powder. The max load of 7.62X54R to min load of 303 Brit is 8-12gr. The max load of 7.62x54R to max load of 303 Brit is 4-9gr. Reducing the 7.62x54R load by 6gr from the higher pressure loads would still be over max of the 303 Brit without any build up. I would really be concerned with just taking this unknown powder and as a blanket statement say to reduce by 6gr and load it up.
Another thing to consider is that OAL issue, the 125gr steel core 7.62x39 bullet is the same length as the 150gr spitzer lead core .311 flat base bullet, so your are still putting that 125gr the same distance into the case as the 150gr. Take this into account when you use the 150-154gr 7.62x54R bullet, if it is a steel core then the bullet will be long and the internal volume of the 303 Brit case will be closer to that of a 180gr bullet rather than a 150gr bullet, so this will have an impact on the pressure, how much? I do not know.
Not saying not to do this, just do your own research before pulling the trigger with a chamber that close to your face, you are responsible, not some guy online.
Any thoughts on taking 20rds of 7.63x39 and bumping up the powder a bit?
7.62x39 has a narrow burn rate powder band, so looking at max loads of powder in 7.62x39 you are around 28-30gr, those same powders min loads in 303 Brit 125gr are 41-42, 25gr seems really light here.
Would it not be better to use the powder at around 15rds of 303 Brit from 20rds of 7.62x39? That would be around 40gr, but this would be a work up of course.
The 7.62x54R is another weird one, for the same powders between the two rounds, 150gr, the difference based on published recipes is 5-9gr from minimum load to minimum load with the 7.62x54R having more powder. The max load of 7.62X54R to min load of 303 Brit is 8-12gr. The max load of 7.62x54R to max load of 303 Brit is 4-9gr. Reducing the 7.62x54R load by 6gr from the higher pressure loads would still be over max of the 303 Brit without any build up. I would really be concerned with just taking this unknown powder and as a blanket statement say to reduce by 6gr and load it up.
Another thing to consider is that OAL issue, the 125gr steel core 7.62x39 bullet is the same length as the 150gr spitzer lead core .311 flat base bullet, so your are still putting that 125gr the same distance into the case as the 150gr. Take this into account when you use the 150-154gr 7.62x54R bullet, if it is a steel core then the bullet will be long and the internal volume of the 303 Brit case will be closer to that of a 180gr bullet rather than a 150gr bullet, so this will have an impact on the pressure, how much? I do not know.
Not saying not to do this, just do your own research before pulling the trigger with a chamber that close to your face, you are responsible, not some guy online.
For the cost of powder why not buy 1lb and load with known powder, I know you can use surplus and the 7.62x39 has a narrow burn rate band but you are throwing an unknown in there. On top of that when you go to the 7.62x54R you are looking at a round with a significantly higher pressure and a significantly more diverse powder burn rate, so more unknowns.
Buying your own powder and putting a minimum load under the 125gr pulled bullet is going to add an extra quarter, still looking at $0.50/shot instead of almost $1.50 now. If you go with H4895 you can reduce the load to 60% of the MAX load, which will give you about $0.15 extra or around $0.35 / shot with a known powder instead of something you have no clue about.
The link below is for the data sheet on light loading H4895, this is from the manufacturer.
https://www.hodgdon.com/wp-content/uploads/2016/11/h4895-reduced-rifle-loads.pdf
I have 7.62x39 corrosive and I will be doing this for my 303 Brit to have some fun.
It is obvious you are starting out, that is ok. This should have been posted in "Reloading" as that is what it is, "Bullet Making" is casting or forming the bullet, not making the loaded ammunition.
As an aside, you said you loaded this into a military pullet 303 Brit and shot that, I get that you would make a lighter recoil round but you have now shot a corrosive primer in your 303 Brit and you should be cleaning your gun as you have. The cordite military rounds are safe to shoot, millions have been shot and I highly doubt you would shoot enough of those to effect your barrel in any way. Just remember to clean out the corrosive salts.
Guys have been doing these "Mexican Match" loads for decades.
It makes sense that simply swapping over the powder and bullet from the 7.62X39, and loading it in 303 Brit would lose about 300 fps.
No concern about "flashover" - the powder used is in the H322 burn range and not susceptible to that.
It makes sense that simply swapping over the powder and bullet from the 7.62X39, and loading it in 303 Brit would lose about 300 fps.
No concern about "flashover" - the powder used is in the H322 burn range and not susceptible to that.
Oh relax. It was tongue in cheek.
One thing you may want to consider is that the 7.62 bullets are steel or bimetal jacketed. I would shoot a boatload of them through a chrome lined $169 (remember when they were that price?) sks, but not my Enfield.
Oh...and not to be a stickler for details, but "Mexican match" is US M852 7.62x51 Nato Match.
Cool, I was waiting for someone to say that.
I have more concern about taking the 7.62x54R ammo and doing the same, someone actually suggested on here once to not even reduce the powder charge and that scared the crap out of me.
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What a great way to reload the 303.
Oh relax. It was tongue in cheek.
One thing you may want to consider is that the 7.62 bullets are steel or bimetal jacketed. I would shoot a boatload of them through a chrome lined $169 (remember when they were that price?) sks, but not my Enfield.
Oh...and not to be a stickler for details, but "Mexican match" is US M852 7.62x51 Nato Match.
Steel or bimetal cases won't destroy your rifle. They are not hardened steel or anything. Plus, as far as I am aware mosins were never chrome lined and i don't see anyone worrying about bimetal jackets in them.
Now to whoever said cordite ammo is safe to shoot, I disagree. It's old, which in itself isn't an issue, but poor storage conditions can lead to degraded powder which will detonate rather than burn. There is a story around here about a box of old ammo that blew up two enfields, and sent one person's kid to the hospital in a helicopter. I can find it when im home if you want, or just search for it...
edit - here is the story.
https://www.canadiangunnutz.com/for...rue-story-of-the-possible-dangers-of-old-ammo
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I tried using 7.62x39 in 2 groove barrel LB No4-no joy.Scatter gun.I also tried that in No1Mk3 with 4 groove barrel-way better but I had to up the charge by about 4 Gr to get decent group at 100yrd.
For the trouble I much prefer Lee 312-155 and 13Gr Read Dot.Easier to make,likely cheaper and more accurate.
For the trouble I much prefer Lee 312-155 and 13Gr Read Dot.Easier to make,likely cheaper and more accurate.
Only easier and cheaper if you cast. If you aren't a big fan of hanging around molten poison, then its probably cheaper to do the x39 takedown ammo. Keep in mind, the takedown ammo includes the powder and bullet cost.
It's a great way to keep shooting an Enfield for cheap. I've been doing it for about a year now, but I don't use the surplus powder. That said, if you can find a source of pulled down surplus bullets, you can save yourself the effort of pulling down surplus rounds and disposing of primed steel cases.
