.308 dia. bullets in 7.62x54r - input request

[_N4Z_]

I've got some 168gr Sierra HPBT's in .308 diameter I am going to test in my Finn M39.

To date all I've ever used is .311's, but this one has a right tight bore dia. (.298"), so I am going to see what it can do with the smaller rounds.

Have several powders available for this caliber (Varget, H4895, IMR4895, IMR4350, IMR4320, RL-15)
Will be loading new Lapua brass (.308 necks)

I am looking for any good load info from those with first hand knowledge only.

Thank you.

 

[Cosmoline]

Not Sierras but I've worked up some loads for the Barnes 168 grain .308" TSX out of my 1970 M39. The best to date is 45 Grains of IMR 4064. That gave me 1" groups at 50.

The D166 bullets from Lapua also do very well in M39's.

Varget is another powder you might try. Also IMR 4320

 

[_N4Z_]

Thanks for the feedback Cosmoline. I was pretty sure you were one of the ones who had used the .308's.

 

[FROGO207]

I loaded up 50 or so with 150 gr FMJ and tried them out. None were as accurate as my .311 bullets.

 

[juniustaylor]

In the Finn rifles, the .308" diameter bullets should be used. Using larger diameters can have a big impact on the pressure generated. The actions of the the Mosins are tough, but I'm just going by what the load manuals say.

 

[CHEVELLE427]

USED .308 IN MY SKS all went good, even some 110 .308 rn

 

[Gadzooks Mike]

I've shot .308's out of my M44. They do ok, but not as accurate as the .311's. They're still good for minute of beercan plinking.

 

[Cosmoline]

Look at the OP. We're talking about a very specific rifle and load here.

In the Finn rifles, the .308" diameter bullets should be used. Using larger diameters can have a big impact on the pressure generated. The actions of the the Mosins are tough, but I'm just going by what the load manuals say.

Different Finn Mosins have different diameters. The narrowest are the pre-war models some of which are down to .309" or .3085" The post-1939 Models including the M39's, the late model M91's and the M30's are not as tight. These tend to be around .310" You will not have a safety issue firing .311" bullets in these rifles, which represent 90% of the Finnish rifles out there. I also very much doubt you'd have any safety issues in an M28/30 or other early Finn with .311" bullets if its stamped with the "D" indicating the "D" chamber. The Finns shot a LOT of captured USSR ammunition.

 

[juniustaylor]

Cosmoline...

I was looking at the OP's post that said the bore diameter was tight at 0.298". However, after research, I have saw that the M39 shot .310" bullets. His .298" number must be from land to land, not groove to groove which would be roughly .300"

Thanks... and sorry for not contributing much worth in this topic.

For load data, you could possibly use info for the 7.65x53 Argentine/Belgian Mauser. Very similar compared to the 7.62x54R.

 

[_N4Z_]

follow up - .308's tested

So I loaded up 9 SierraMK 168gr BTHP (.308 dia.) in some brand new Lapua 7.62x53r cases and took them for a ride down the barrel of my M39B.

For those that were lamenting the bore dimensions, they are .298 - .311 on this particular rifle.

Ended up loading 44 grains of H4895, used Fed 210M, COAL of 2.980".

Rifle benched and sandbagged. Fired two foulers, followed by 9 on target.

Over all spread of holes was a touch over 3 inches at 100 yards. No optics.

7 of the 9 put together a pretty nice group IMO.


To me the use of .308 rounds with this rifle seems doable. With fireformed cases and tweaked loading I think this group could be tightened up considerably. May need to dig deeper here.
May get some longer, heavier rounds to try next.

Here's a pic of todays test.

 

[CHEVELLE427]

nothing wrong with that pic