My .38-55 has a groove of .376

30 May 2003, 06:42

<Win94>

Fellas, i just got off the phone with Glen Jensen at winchester Tech. He stated that my 1980 win. 94 has a bore of .368" and a groove of .376" with a 1 in 15 twist. My current plain based bullets are .379 i have tried them and they are fairly accurate but as you can see in another post i went a little hot and leaded my bore somewhat. Any suggestions on shooting a plain based .379" in a .376" barrel?? If anyone is interested he is at 1-800-945-5237.

30 May 2003, 07:05

FAsmus

Mark,

you ask: Any suggestions on shooting a plain based .379" in a .376" barrel??

F: The difference of 0.003 between bullet and groove diameter is not a major problem for your rifle unless accuracy itself suffers unduly, and you say that this is not the case.

I used to have a 40/65 with a conventional 0.409 groove diameter. Due to unusual throating I finally got my best accuracy with bullets of 0.414 diameter.

Shooting cast lead bullets is full of variables, bullet size being one of many. I happen to think that a fellow may tailor a load/rifle to accommodate any minor difference in the so-called "ideal" of shooting a bullet just 0.001 over groove diameter for best accuracy. Such things may be dealt with by tailoring the load to your particular set of components.

Good afternoon,
Forrest

30 May 2003, 07:28

Leftoverdj

quote:
Originally posted by Mark Marchand:
Fellas, i just got off the phone with Glen Jensen at winchester Tech. He stated that my 1980 win. 94 has a bore of .368" and a groove of .376" with a 1 in 15 twist. My current plain based bullets are .379 i have tried them and they are fairly accurate but as you can see in another post i went a little hot and leaded my bore somewhat. Any suggestions on shooting a plain based .379" in a .376" barrel?? If anyone is interested he is at 1-800-945-5237.

Unless you sent your rifle or a slug from your rifle to Winchester, you still don't know what your bore is. All a tech rep can do over the phone is to give you factory specs and a thou or two off either way would not surprise me any.

If I am misunderstanding and your bore has actually been slugged and measured at .376 groove, .379 bullets should work as long as the loaded cartridges chamber freely. That's a little big and. in your boots, I would send Lee Precison a check for $30 and ask them to make a .377 sizing die. It'll take them a couple of months to get around to doing it and you can play with what you've got in the meantime.

You haven't given us any load data. Plain based bullets are generally reckoned to be limited to 1600 fps, give or take a little depending on the rifle and exact laod.

The easiest thing to do is to just back off on your load a bit. If you don't want to do that, you can add a SoftChek. That's a specialty wax that comes in thin sheets. You just place a sheet over the case mouth after you/ve added the charge and press with your thumb. Then seat the bullet bullet. This usually cures slight leading problems in a load.

A variant on this is the grease cooky. There are lots of ways to do this, but since you are shooting a .38-55, you might want to buy a 3/8s hole punch from the nearest hardware store and cut a bunch of wads out of felt. Just dip the wad in melted lube and set on a cookie sheet to harden. After they are hard, you can heat the cookie sheet just a little to make them easier to get off.

You just seat the wad flush with the case mouth and seat the bullet on top. The wad should be a tight fit in the case so it stays in contact with the bullet base.

30 May 2003, 17:51

woody1

Mark, as you've been told by previous posters, clean the lead out with chore girl/boy pot scrubber strands on a brush. You need to slug your bore and you need also to give us some load data to digest. Factory bore specs are one thing, actual is sometimes quite different. I don't know what velocity you're trying for, but you should be able to get 38-55 velocity fairly easy with plain base bullets. I shoot a 375 Marlin (375 Winchester) with a microgroove barrel and my hunting loads are 1800 fps with a Lyman 375248 pb bullet. While not one hole accurate, accuracy is plenty good for hunting and I get very little leading. Regards, Woody

31 May 2003, 20:20

z1r

The bore size is not an issue as long as, like leftoverdj said, you have adequate neck clearnace.

Reduce velocity.

I shoot .313" bullets in my .308" barrelled .32 H&R with no problems and accuracy is fine. I'm pushing a 100 grain plainbase at 1600 fps.

17 June 2003, 07:06

<Jï¿½rgen>

I had an experience with my 38-55 (1903) Winchester like this , I figured : What the hell , this old stove pipe has a shotout barrel or the factory tolerances are sloppy anyway ....WRONG !I ordered a .379 sizing die and was unable to close the action even halfway ! Necksize was way too big with the 379 bullet and even the 377 bullet is really tight , but shoots like dream (comparatively speaking) with no sign of high pressure, slug your bore or you`ll be fishing in mud water ! [Big Grin]