Reloading 7.62x39

[lexnaturalis]

I knew I'd have more questions.

I just bought (and read) the Speer Reloading Manual (#14 I believe). I was happy to see that it had data for the 7.62x39mm, but when I went to some of the local stores they didn't sell any of the powder listed in the book. I'd really hate to have to buy powder online because I'd have to pay an extra Hazmat fee in shipping.

Is there any other (reliable/safe) source of load data that might include more propellants to see if I can find data for any of the powders I have locally? Or does Speer pretty much cover it all?

[daschnoz]

I understand exactly what you are saying. Good luck finding AA1680 on any local retail shelf.

x39 is a strange animal. There's not a whole lot of case volume for the bullet weight being fired. The "useful" burn rate range is somewhat limited.

Check out
http://data.hodgdon.com



IMR3031 will work well and also works well in larger calibers with a wide range of bullet weights.

IMR4198 or H4198 are pretty decent, but are more for smaller rifle calibers, or the really light bullets in larger calibers.

Reloader 7 works well (my powder of choice for this round) and can also be used in 308WIN with 150gr bullets and lighter.

If you need data, let me know. I have a bunch for this caliber.

[mauser]

daschnoz has it right.
When I saw your question my first thought was the Hodgdon load data site. They list loads for Hodgdon, IMR and Winchester powders. You'll find load data there for powders that I know you'll find on the shelf at your local shop.

[lexnaturalis]

The bullets I just purchased are 124gr FMJ and the Hogdon site uses 125gr. Does the 1gr difference in bullet weight affect the load?

Edit: I should note I'm loading for the SKS, if that matters at all.

[mauser]

Short answer is no, it won't make a difference.

Longer answer; the manufacturing tolerance is such that you may find 124 gr bullets that weigh as much as some 125 gr. and 125 gr that weigh less than some out of a box of 124 gr.
Match grade bullets have tighter tolerances.
going lighter by a grain or 2 is safe as far as I'm concerned. When you use a heavier bullet is when you start to increase pressure. If you start with the starting load and work up while watching for pressure signs there shouldn't be any problem at all.
I'm not saying that one grain of weight is insignificant in terms of reloading, but in terms of bullets, lighter is better than heavier and if you're not working with "hot" loads to start with you shouldn't have any problem with a 1 grain deviation either way from the published data.

[lexnaturalis]

Thanks for the explanation. Since I'm brand new to reloading I didn't want to do something stupid and ruin my gun or hurt myself.

[daschnoz]

General rule of thumb (if you intend to keep them), don't jump right to the maximum load listed. Always start low. That doesn't necessarily mean that you have to start at minimum either. As you get more experience, you'll have a better feel of what you can safely get away with.

For my x39 loads, I use 125gr Speer TNT bullets with 123gr data (for 0.310" dia bullets). This is where a bit of experience comes into play. In general, AK barrels will slug anywhere from 0.309" to 0.311" - some slug larger. The Speer TNT is 0.308". That means that there is less bullet contact with the grooves, thus, less friction in the barrel. Less friction means that less energy is required to push the bullet down the barrel. As a result, to the internal ballistics, the bullet appears to weigh less than it actually does. I still started low and worked up however.

Now, before I start getting flamed, I'm not telling you to be reckless. Use your head. If the min load is say 25.3gr, and max is say 29.4gr, I would start at 26gr. It's still on the low end of the scale. What I would NOT do is start at 29gr. That's too close to the max, and may be over max for the particular powder lot, case, primer, and bullet combination being used.

Here's what I end up doing - find data for the next closest bullet weight. If the bullet is lighter than mine, I start exactly at the minimum and work up. If the bullet is heavier than mine, I use the data as is.

A couple of examples

I have ------------Load data I use
147 ---------------- 150
152 ---------------- 150 (start at min)
160 ---------------- 155 (start at min)
165 ---------------- 168
172 ---------------- 168 (start at min)
175 ---------------- 180

See the pattern?
If your bullet falls exactly in the middle of the load data bullets, use the data for the heavier bullet.

Hope this helps.

[RaisedByWolves]

Originally Posted by daschnoz

Here's what I end up doing - find data for the next closest bullet weight. If the bullet is lighter than mine, I start exactly at the minimum and work up. If the bullet is lighter than mine, I use the data as is.

Check that.



What kind of economy do you see over store bought 7.62?


Where do you find your brass?


.

[lexnaturalis]

Originally Posted by RaisedByWolves

Check that.
Where do you find your brass?

For me, the only place I could find brass at was GunBroker. Everywhere else was sold out (or outrageously expensive).

[Warpt762x39]

Originally Posted by lexnaturalis

For me, the only place I could find brass at was GunBroker. Everywhere else was sold out (or outrageously expensive).

*cough*wolf*cough*