7.62x54R Bullet question

[pklin1297]

Hello all,

On my latest edition Sierra reloading manual, there are many pages for the 7.62x54R round which is great, but all the loads call for the .308 diameter bullet. However, I have read from different sources that my 91/30 might actually be closer to the .310-.311 diameter, as most people have found out after slugging their bores... So my question is, should I load up rounds with the .308 diameter bullets or the .310 - .311 diameter bullets? Is there an easy way for me to "slug" my own bore to find out?

Also, if I end up needing to work up .311 loads, where can I get load data for that? Could I get them from .303 or 7.62x39 data tables?

Any help would be greatly appreciated!

[dustoff31]

Personally, I always try to use the bullet that most closely fits the bore. It's particulary important if you are shooting for accuracy. For plinking, it's probably not all that important for very small differences. Here's a link that describes the process for slugging a bore.

http://www.surplusrifle.com/reloading/slug/index.asp

You should be able to use the same data for larger diameter bullets, so long as the bullet weight doesn't change. That is, a .308 165 gr bullet = a .312 165 gr bullet.

Please don't ever use reloading data from a different size cartridge case! Not healthy!

[pklin1297]

Good deal, thanks!

[sunborder]

Slugging your bore is easy. I was intimidated, but got it right the first time. Go to surplusrifle.com and look for the article on it. If you use starting loads, you should have no problem, even with a SLIGHTLY larger CAST LEAD bullet. Do not use larger jacketed bullets than the bore. Most Russian Mosins can use the same bullets as .303 british (.311). Finnish Mosins generally use the .308 or thereabouts.

My mosin is .312". Slug the bore, and use rounds that fit. Smaller is okay, but will have less accuracy. If using unjacketed lead bullets, smaller diameter may cause lots of leading, quickly.

[762cavalier]

Finnish Mosins generally use the .308 or thereabouts.

There are only one or two models of Finns that use a .308 bore. Both my M28 and M39 have a .310 bore.

[pklin1297]

Will be shopping for the lead sinker and dowels to slug barrel tonight.

What size sinkers did you guys use? I've read 1/8 sized sinker, but also #9 sinker, which is by ounce (1/4). Probably gonna drop by Bass Pro on my way home since they will probably have the best selection, but just want to make sure I get the right egg sinker size...

[pklin1297]

Slugged the bore tonight and found groove diameter of .312, and bore diameter of .300. According to these readings, I should be able to shoot .310 and .311 jacketed bullets correct? Just want to make sure... Here is the diagram I got from another slugging tutorial site:

[762cavalier]

yup you can use the same bullets that are made for .303 brit and 7.7 jap

[pklin1297]

Great!

[sunborder]

There are only one or two models of Finns that use a .308 bore. Both my M28 and M39 have a .310 bore.

Hence the word "thereabouts". Russians generally START at .310 and go up to .316 or so without being abnormal. Don't see too many Finns like that. It could happen, but id guess you would be lucky to get a Russian with anything less than about .312 unless it was prewar.

[pklin1297]

Any suggestions on brand of bullet and weight that you've tried and worked well?

Per the last owner of my 91/30, apparently Wolf Gold 148 grain bullets shot very well in it, but I believe that is still .308 correct? Am thinking about the Sierra 174 grain .311 boat tail to try... Anything else I should load up?

Oh and are there any brass other than Lapua, Norma, or other expensive brands available for this cartridge?

[6079Winston]

Without trying to make things more complicated than they are, it is not always necessary or desirable to shoot groove diameter bullets through rifles. This is beause of the reduction of area taken up by the lands. As a bore diameter bullet passes through the leade it is engraved by the rifling with the reduced area available causing the bullet to lengthen. In an oversize bore with tall and wide lands, the bullet might expand to fill the bore and not lengthen as much, since all that bullet material has to go somewhere. This might explain why "undersized" bullets shoot well in some rifles. My advice would be to use .308" bullets if they shoot well in your rifle, if only to avoid getting a larger expander ball and stocking odd sized bullets.

[pklin1297]

Thanks 6079Winston!

Haven't tried Wolf yet per the previous owner's experience but have tried some surplus that were being sold at Fowler's. I didn't know the bullet weight and it didn't shoot well at all.

I will load some .308s and .310s to see for first batch.

[sunborder]

Czech silvertip surplus will do fine. Just clean the bore/bolt with windex when done. Otherwise, you can try Wolf Gold/Hotshot (it's all Prvi Partizan, just a different box). My Mosin at .312 shoots the .311 Prvi JSP from Grafs just fine, and the Lee TL-312-160-2R into 2" at 50yds. Could be better, but I can't shoot straight.