[civilian75]

Hi, I am new in the forum, and I am also a pretty new to reloading with Pb boolits. I have a very basic question. I want to load 170gr LMN .313" GC Beartooth Bullets (BBs) on a 7.62x54R Finn M39 in as fast as I can. I just can't figure how fast I can push 'em w/o running into leading issues. My guess the ceiling is 2100-2200, but I'd like so know if 2200-2400 is feasible. My experience is limited to 405gr LFN 45-70. Never tried to push anything above 1800fps.

Also, I'd love to hear from anyone who has already achieved some success with a similar setup (i.e. what powder, primer, and charge combo over a 7.62x54R BBs over 27" .3115" dia. barrel).

 

[kdub]

Depends on how pristine the bore conditions are. A nice, smooth bore with no defects can shoot to higher velocities before leading. Also, depends on hardness of the bullets.

In my experience with cast rifle bullets, anything over 1800 fps can cause lead buildup with normal bores and bullets. Marshall Stanton, owner of BTB and the board, says 2400 fps with his bullets in a good bore. I've never pushed them that hard.

 

[MikeG]

I've run to 2300 in the .30-30 and .35 Rem with no issues. That is with good smooth bores which are only 20" long.

Note that your longer barrel may present it's own challenges.

Let us know how it goes.... always good to get new data.

 

[civilian75]

Note that your longer barrel may present it's own challenges.

So it sounds like running fast cast bullets thru a long 27" is not a good idea. Does anyone care to elaborate? Thanks.

 

[unclenick]

Actually, if the bore is smooth it should be easier than in a short barrel. The reason is you have more inches to pick up speed, so you'll be able to use a little less peak pressure, and that's going to minimize leading.

Firelapping makes a bore smooth, and is frequently done to guns that will shoot cast bullets. You'll want to look into doing that if you haven't already.

Veral Smith has gotten cast bullets up to 3000 fps, but points out you really need the right lube, the right bore condition, the right bullet hardness, etc. Smith points out that watching pressure signs gets really critical up there, and that changing barrel temperature can have a more dramatic effect on pressure with cast bullets than with jacketed, so this all must be approached with great care.

Firelap, use those hard gas checked bullets, and I think you may well surprise yourself with what you can do.

 

[MikeG]

I mentioned the bore length because some folks find that longer barrels seem to "run out" of lube, at times. Mine are all short so not an issue for me, but it comes up on the forum from time to time.

Hope your Finn has a good barrel. Those Mosins can be rough after having been through a war, or three.

 

[unclenick]

Good point. I'd thought to suggest p-wads, but that it might make the thread more complicated. They were originally LDPE sheet cut to bullet size wads, but Merrill Martin always said the stop all signs of leading. Apparently a certain amount will melt off and help lay a lubricating layer in the bore. Might be an interesting experiment to try. Still won't get him out of firelapping the bore.

 

[TMan]

As noted, bore condition is very important, at least for more than a couple shots. Getting bores smooth/broken in is a project requiring care, and less is more.

I have a pair of Whelen's that shoot incredibly well. Literally varmit rifle accuracy. The bores are very rough, and foul quickly with jacketed bullets. Passing an oiled patch down a cleaned barrel tells all. A recent purchase of the BT 210gr cast foul quickly even with Trail Boss, I doubt they are going much more than 1800-1900fps. Swapping ideas on another forum, I think it's time for fire lapping, and I was going to use the cast bullets for that operation.

I have an older Marlin .30-30 Microgroove, on the other hand, that can go all day with another brand of cast bullets that don't even have a gas check on the base, loaded with jacketed volumes of W748. The bore on that rifle is smooth as glass.

It depends, but mostly it depends on the bore.

 

[unclenick]

TMan,

You don't want just any cast bullet for firelapping. See my post #2 here.

 

[civilian75]

Thanks for all the info.

The Finn barrel is is very good shape. I obtained an un-issued rifle and I have not fired 400 rounds thru it.

I am not sure I want to lap the barrel, at least not yet. I enjoy shooting Cu jacketed on this rifle. I am not ready to "dedicate" it for Pb cast boolits.

I am leaning towards starting slow, say, 1500-1700fps, see how the rig works for the intended application, and then slowly increase mvs.

I'll be loading .312 or .313 most likely (slugged .311). What does one use as an "expanding die" ? My cast boolit handloading experience is limited to 45-70.

thanks again...

 

[unclenick]

You can buy the Lee Universal Expander. You can also get a Lyman M die for 31 cal.

 

[Swany]

The one hole group at 1700 fps beats the shotgun pattern at 2400 fps.

Work your load up until you reach the best accuracy and then quit. After practice with that rifle and get used to its trajectory.

 

[civilian75]

Swany, I can't say I disagree with you. I am seeing at the range what guys can do with a 208gr in a 1903 Springfield with 2400 and AA5477 going at around 1600fps. If I find a load that accurate for my M39 I will feel very fortunate.