158 grain Rf out of 4 inch barrel 1:16 or 1:18.5??

[jtwodogs]

The major bullet I will be shooting is a 158 grain RF out of a lee mold.
The revolver will have a 4 inch barrel with a choice of 1:16 or 1:18.75 twist.

Which twist rate will give optimum stability, and ultimately the best accuracy?

[Outpost75]

Back in the days when we built custom PPC revolvers the winning shooters were all using 1:14 or faster. Firing Remington or Winchester 158-grain LRN, SWC or 148-grain wadcutters we expected 2-inch 24-shot groups at 50 yds from a Ransom Rest.

Alot of guys screwed Colt Python barrels onto S&Ws.

For a pure wadcutter gun only .38 Special with a 1:10 barrel, 6-degree forcing cone and 11 degree crown can't be beat.

[Frank46]

Agree with outpost75 as I have a Douglas barrel blank marked 1x14 twist 38 special. Smythons or smolts were kinda nick names used for S&W revolvers using python barrels. Plus I kinda think Colt barrels are a little tighter in bore diameters. Have a elderly Colt Trooper III in 357 magnum that really likes S&B 158 grain ammo. Frank

[Scharfschuetze]

I agree with both posters above. My PPC revolvers were all 1 in 14" twist barrels. My S&W stock revolvers are accurate enough, but I always wondered about S&W's reason for their 1 in 18.75" twist. At 50 yards, HBWCs often shoot a slightly oval hole in the paper indicating some wobble.

Still, with SWCs and jacketed bullets that twist rate seems to work just fine with about anything you put through it. I even won state level PPC matches a couple times in the service revolver class using stock S&Ws with that twist using the 148 grain HBWC boolits.

My Colt Python and Official Police revolvers have a 1 in 14" twist and my Marlin rifle in 357 Magnum has a 1 in 16" twist. That 1 in 16" twist seems to be a good compromise for accuracy. I guess I'd go with that given your two choices.

[Outpost75]

The reason for S&W sticking with the 18.75" twist in .38 Special was that it was a carry-over from black powder days with the .38 S&W (NOT Special) cartridge and they never changed it over all those years.

Colt went to the 14" twist immediately with the transition to smokeless powder, being led in that direction by conducting extensive accuracy tests at ranges out to 200 yards, assisted by professional exhibition shooters and Camp Perry champions. Prior to 1940 Colt revolvers ruled the ranges at Camp Perry and Bisley. Colt's Officer's Model Target and later Officer's Model Match were used by Col. Edward B. Crossman, Charles Askins and other noted champions of the pre WW2 era.

[Scharfschuetze]

The reason for S&W sticking with the 18.75" twist in .38 Special was that it was a carry-over from black powder days with the .38 S&W (NOT Special) cartridge and they never changed it over all those years.

I suspected that it was due to something shrouded in misty antiquity; much like the Ought-Six to this day still uses the original 1 in 10" twist first used for the 220 grain RNFMJ bullet.

[Frank46]

Much the same regarding the 1x38" twist used by most lever action makers as it was used in the 44-40. This is the normal twist for 44 magnum. Supposedly marlin was going to change this to a 1x20" twist but guess it never happened. Frank De Hass wrote about this years ago and proved that 1x20" twist was way better. Frank

[Scharfschuetze]

Much the same regarding the 1x38" twist used by most lever action makers as it was used in the 44-40. This is the normal twist for 44 magnum. Supposedly marlin was going to change this to a 1x20" twist but guess it never happened. Frank De Hass wrote about this years ago and proved that 1x20" twist was way better. Frank

Yep, it goes on and on doesn't it. Tradition is strong in the shooting sports and industry. Often it's just fine and good, but now and then it's to our disadvantage.

[DerekP Houston]

dang I here I thought I only needed to worry about twist rates on my rifles. Learn something new every day here. Thanks yall.

[Cherokee]

go with the faster twist

[Outpost75]

I suspected that it was due to something shrouded in misty antiquity; much like the Ought-Six to this day still uses the original 1 in 10" twist first used for the 220 grain RNFMJ bullet.

The 1:10 twist is also VERY necessary to stabilize the longer Ball M1, M72 Match, APM2 and M1, M2, M2 Alternate, T10 and later M25 tracers, particularly for machinegun use.

[Preacher Jim]

I use 1x10 for my match 38 spc revolvers. I have tried 1x12 and 1x14 but my best results are 1x10 twist

[Echo]

I agree with both posters above. My PPC revolvers were all 1 in 14" twist barrels. My S&W stock revolvers are accurate enough, but I always wondered about S&W's reason for their 1 in 18.75" twist. At 50 yards, HBWCs often shoot a slightly oval hole in the paper indicating some wobble.

Right - and they won't stay on the paper at 100 yards!

[Scharfschuetze]

The 1:10 twist is also VERY necessary to stabilize the longer Ball M1, M72 Match, APM2 and M1, M2, M2 Alternate, T10 and later M25 tracers, particularly for machinegun use.

It's probably the first time, but I have to disagree with you Outpost. Truth be known, a 1 in 12" twist will stabilize Ball M1 and the M72 Match rounds quite well out to 1,000 yards even in cold temperatures. Match Ought-Six barrels with 1 in 12" twist have proven that more times than I can relate. The tracers, perhaps not, but similar tracers and M118 Special Ball with the same 173 grain bullet (as M1 Ball and M72 Match) in the 7.62 NATO stabilize fine out of a 1 in 12" twist and at a lower velocity. I've shot literally thousands of the tracers through the M14, the M60 MG and the M240 MG and their 1 in 12" twist barrels out past their burn out range of about 900 meters with no issues and fine accuracy both operationally and in training.

No, the 1 in 10 twist in the standard Ought-Six barrels is a holdover from the heavy 220 grain RN first issued as the Thirty Ought Three (30/03) of 1903 until the lighter spitzer bullet of the Thirty Ought Six was adopted in 1906. As you know, the original 1 in 10" Ought-Three barrels were simply set back and the neck of the Ought-Three was shortened to what we now call the 30/06. The fast 1 in 10 twist continues on today due probably to the economy of salvaging thousands of 30/03 barrels and repurposing them as 30/06 barrels. As I recall that 220 grain FMJRN projectile was itself a holdover from the 30 US AKA 30/40 Krag cartridge.

My current Winchester Pre-64 Model 70 match rifle is barreled with a 1 in 12" barrel by choice and it stabilizes M72 Match (173 grain), 190 grain SMKs as well at Berger 185 grain VLDs to a thousand yards with ease. If I keep up with the wind, the light is good and the mirage not too bad, it holds the 10 and X rings easily when I do my part.

[44man]

I am refreshed that some revolver shooters get twists right. I am a twist nut and hate too slow.
Now the 30-06 with 1 in 12" needs shot balls to the wall. 1 in 10" is better for most bullets and velocities we get.
I ran into twist long ago with a 220 Swift where I could shoot a 60 gr Hornady to head shoot chucks over 600 yards while the 22-250 needed a lighter bullet due to a slow twist. Fail at long ranges.
Look at the AR's today for heavy bullets.
But get back to the revolver. I have stated many times a short barrel needs a faster twist then a long barrel.
I never understand why a rifle is brought in to a revolver discussion anyway.