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andym79
08-30-2017, 07:45 AM
Hi guys I am looking at building a rifle in 500 s&w, most barrels seem to be very fast 18 or 19, a BMG is only a bit quicker at 15 some of those are even 20!

Firstly why such a fast twist?

Secondly I am looking to shoot bullet of between 375 (0.84") and 430 (0.96") grain, even the most conservative calculators predict a 32 to stabilize those bullets and some say you might be able to push it to 38, but that a 36 does it okay!

I would rather not twist my cast bullets anymore than necessary, and I think in a rifle pushing those bullets to 1500fps and keeping pressure down should be easy enough. The 19 twist standard gives you a SG of between 5 and 9?

I can get a 25 or 36 twist barrel, the 25 should just about stabilize anything up to 1.4"-1.5" (640-680 grains) by which time you are probably running out of coal in the 500. Why does the 500 come with a twist that in theory can stabilize a 900 grainer if the case were of course big enough?

Ideally I think a 30 twist would be the go, I am not sure if anyone offers that rate?

Even a relatively quick 44 mag often comes with a 20 twist?

If anyone has a 500 S&W I would be very interested to hear from them!

Wayne Smith
08-30-2017, 09:50 AM
I'm not even sure what my Encore is, and I haven't shot it enough to know how well it stabilizes anything! I do have molds for the original 50-70 boolit, I think 300 gr. up to a much bigger boolit but I've forgotten exactly how big. I know I have a 400+ but I'm at work and can't remember precisely.

Moonie
08-31-2017, 11:14 AM
My 500 S&W Encore barrel is from MGM and is a 1-19" 15". I believe the 1-19" is a specification S&W put in place for the cartridge.

chloe123
08-31-2017, 03:16 PM
Out of a carbine and rifle, so not sure the impact of additional length on stability rel to a pistol length, but I think my BHA is 1/24"

TMenezes
09-01-2017, 03:51 PM
Don't stress the faster twist rate, it will work great. S&W put a lot of time and effort into that calibers development and I am sure they know more about it than you or me. John Ross is the recognized authority on this round and he specced out an even faster twist on his special edition revolver. The shorter barrels need a faster twist than the longer barrels. Plus, once you do some extensive shooting with that heavy hitter you will appreciate the slower lighter loads. The slower the bullet is traveling the more twist you need. Look up some of John Ross's writings on the 500, very informative.

I am planning to buy it when I can. For now I enjoy shooting my BFR's in 500 S&W and they have something like 1 in 15 to 1 in 18 twist, can't remember now.

andym79
09-01-2017, 10:46 PM
Thanks for your replies I don't pretend to know more than most folks about anything regarding rifles.

Just thought that an over fast twist especially with cast bullets could hurt accuracy.

I guess I need to decide how big a bullet I want to shoot and how fast and figure twist from there, I guess I just figure that if the 50-70 could stabilise 535 grains with a 28 twist at 1200fps then why does a 500s&w need a 19 to do it with 440 grains at 1500fps?

But if people have shot them and they are accurate I have no reason to doubt them.

Moonie
09-02-2017, 10:15 PM
Thanks for your replies I don't pretend to know more than most folks about anything regarding rifles.

Just thought that an over fast twist especially with cast bullets could hurt accuracy.

I guess I need to decide how big a bullet I want to shoot and how fast and figure twist from there, I guess I just figure that if the 50-70 could stabilise 535 grains with a 28 twist at 1200fps then why does a 500s&w need a 19 to do it with 440 grains at 1500fps?

But if people have shot them and they are accurate I have no reason to doubt them.

Has more to do with length than weight.

MT Chambers
09-03-2017, 06:44 PM
I have bullets up to 700 grs. for the .500 Smith and it would need those faster twists.

JimP.
09-03-2017, 08:52 PM
my rifle has 1:20 barrel, it shoots 370 gr, 440 gr, 500 gr and 565 gr bullets very well. 20 grs Bluedot for all the loads....black powder also works, 65.0 grs and the 500 gr bullet gives 1100 fps......enjoy JimP.

45stomp
09-04-2017, 02:45 PM
Not a 50 cal, but the first 45-70 I built is a 1-14"(spec rate for .458 winchester) twist and shoots great with cast at a variety of speeds and bullet temper. I am not convinced that twist rate(assuming it is tight enough to stabilise) is all that critical. YMMV

Darcy:drinks:

andym79
09-06-2017, 03:19 AM
Thanks for your replies guys, I guess a lot of what twist you want comes down to what you want from the rifle. If you want to shot shorter for caliber bullets and moderate velocity then slow is the go if you want to shoot the monsters then you need a fast twist.

I guess I just figure to shoot standard length s&w bullets from a rifle something like a 1:25 should be fine.