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CAS TOPICS => NCOWS => Topic started by: Two Bit Charlie on February 14, 2014, 01:34:23 PM

Title: What barrel twist for 38-55
Post by: Two Bit Charlie on February 14, 2014, 01:34:23 PM
I'm building a 1894 Winchester into a rifle caliber lever action side match gun.  I need to reline the barrel in 38-55.  Any recomendation for the twist.  I plan on using 250 to 260gr bullets, probably no farther than 200 yards. I'm offered either 1-18" or 1-14".  I believe the 1-18" was standard with the Winchester and the 1-14" would be for the heavier 300+ gr bullets.  Would the 1-14" stabilize the smaller bullets?  I do have a mold for the heavier bullets.  Would they work any better for this application? Any help will be appreciated.

Two-Bit Charlie

Title: Re: What barrel twist for 38-55
Post by: rbertalotto on February 14, 2014, 01:40:59 PM
All depends on what length bullet you'll be shooting.

And that will depend on the range and target. If using the 38-55 for Silouette shooting you'll want to shoot the 330gr bullets and they are very long and need a fast twist.

For simple plinking and under 200 yds target shooting, most folks go with the 250g offerings and a much slower twist will do.

Once you know the bullet, measure its length and then there are on-line calculators to determine the twist needed to stabilize the bullet.
Title: Re: What barrel twist for 38-55
Post by: Blair on February 14, 2014, 02:38:32 PM
Charlie,

What powder do you have in mind with your loading?

The 38-55 is a BP designation. However, it is introduced early into the smokeless powder time period.
The 1894 Winchester Leaver guns will be more sensitive to the OVA finished cartridge length with the long heavy bullet. These bullets will reduce the amount of powder the case will hold if you intent to use BP, and still get them to feed through the action.
Just a thought?
My best,
Blair
Title: Re: What barrel twist for 38-55
Post by: Two Bit Charlie on February 16, 2014, 05:52:24 AM
Thanks for the help guys.  I've decided on the 1-18" twist.  I got a 320 gr Lyman Mold that puts out a 1.175" long bullet (measured the mold).  This is a special made mold that had been discontinued years ago.  Anyway, I used the formula for finding twist rate, and it came out to 1-18".  I will be using smokeless powder.  I also have a 249 gr mold (did not measure length) which should shoot better in the slower twist of the 1-18" compared to the 1-14".

I bought a new barrel from Numrich Arms for this build (1894 Winchester).  It has a twist of 1-10".  What's with that?  That's the reason we're relining it!

Thanks Again
Two-Bit Charlie
Title: Re: What barrel twist for 38-55
Post by: rbertalotto on February 16, 2014, 01:38:59 PM
I just went through this for a 38-55  Ballard I'm rebarreling. The bullet I shoot is a 335- 340g Lyman #378-674. It measures 1.309 LOA

I'm ordering a 1-12 barrel as I'd rather be a bit over stabilized than right on the edge.

I think a 1-18 it too close for the bullet you will be shooting. I would go with at least a 1-14...but just my opinion.

Good luck with it whatever you decide.
Title: Re: What barrel twist for 38-55
Post by: Sir Charles deMouton-Black on February 16, 2014, 03:19:10 PM
Quote from: rbertalotto on February 16, 2014, 01:38:59 PM
I just went through this for a 38-55  Ballard I'm rebarreling. The bullet I shoot is a 335- 340g Lyman #378-674. It measures 1.309 LOA

I'm ordering a 1-12 barrel as I'd rather be a bit over stabilized than right on the edge.

I think a 1-18 it too close for the bullet you will be shooting. I would go with at least a 1-14...but just my opinion.

Good luck with it whatever you decide.

I agree; I have a Hi-Wall rebored with 16.5" average gain twist, and even that is marginal for a 275 gr (Lyman GC for .375H&H)  It is better to be a bit tight.  Especially if it is good scotch! :D
Title: Re: What barrel twist for 38-55
Post by: French Jack on February 16, 2014, 03:52:36 PM
In the model 94, the OAL is critical for feeding.  You really won't be able to use over a 300 gr. bullet, and some of those will be too long, depending on the shape of the nose.  Too fast a twist is not ideal with lead bullets.  I would not go with anything faster than a 1-16" twist.

But-- suit your self.
Title: Re: What barrel twist for 38-55
Post by: Blair on February 16, 2014, 06:17:31 PM
Charlie,

Should you choose the heavy/long bullet... I would highly recommend the faster ROT.
1-16 is a good average for heavy bullets.
Something lighter,,, 250 to 260 in the 38-55, 1- 18 to 1-20 seems to work best, but may not give you the range you want.
Light bullets, slow ROT, and long range don't seem to work well together. (for BP loaded rounds)
My best,
Blair