[SkyPup]

I have a Thompson Center Encore rifle with a Match Grade .22 long rifle barrel.

I have been wanting to get a .223 barrel and a nice scope for this rifle but when I look at the T/C catalog all I see is 24 or 26" barrels with a 1:12" twist?

The reason I wanted to get the barrel in the first place was for long range heavy 75 grain handloaded bullets, not a varmit rifle for 35-55 grain bullets.

Does anyone know off hand what weight of bullets a 1:12" twist maximum is good for?

Maybe I will have to contact the T/C Custom shop to see about a rifle barrel with a 1:7" twist rate?

 

[restoring]

I poked around and saw this:

http://www.snipercountry.com/hottips/TwistRate.htm

 

[ullie]

The reason I wanted to get the barrel in the first place was for long range heavy 75 grain handloaded bullets, not a varmit rifle for 35-55 grain bullets.

Does anyone know off hand what weight of bullets a 1:12" twist maximum is good for?twist rate?

...what will determine the "stability factor"...that is...the gyroscopic stability of the projectile in flight "primarily" are bullet length and to some degree weight...the projectile's configuration and it's center of gravity...the twist rate and exit velosity...the twist rate and actual exit velosity will determine the projectiles rotational speed...there are other factors such as air temperature and air density which will affect this relationship...

...longer...heavier projectiles need a greater rotational speed for any given caliber...in .223 caliber...a barrel with a 1 in 12 twist rate will generally stabilize bullets up to 55 grains...this is dependant upon the actual exit velosity though...the greater the exit velosity...the greater the rotational speed of the projectile...the more likely that you will approch optimal gyroscopic stabilization...for the best accurary under the widest range of atmospheric conditions...40 to 50 grain projectiles do best...

...a 1 / 12 twist rate "will not" stabalize the longer and heavier 75 / 77 grain projectiles...the optimun twist rate for these projectiles would be 1 / 8...and depending on the loading and atmospheric conditions...a 1 / 7 may be on the fence...and "may" overspin the projectiles out of the longer 24 and 26 inch barrels if the load developes too great an exit velosity...

 

[SkyPup]

Thanks so much for that great information.

From what I understand, since the barrel is much longer, that a 1:7 maybe too much for the heavier hunting bullets and that a 1:8 would be preferred.

I will contact Thompson Center Arms and see if they have available a custom barrel with a specified 1:8 twist for my purposes.

I would like to have a scoped tack driver single shot .223 that I can shoot my handloads for my 556's in and I thought this T/C Encore rifle would be the best way to go about it.

I will look around at some of the other .223 single shot rifles with 24"-26" barrels and see what twist rate they have, like the Ruger #1.

Also, I do have an older Thompson Center Contender Pistol with a scoped 14" ,22 MAG barrel and a scoped 10" .44 MAG barrel, and I may get a .223 barrel for this single shot pistol too.

That way I could have TWO shots on me in the woods!!! 8)

 

[ullie]

From what I understand, since the barrel is much longer, that a 1:7 maybe too much for the heavier hunting bullets and that a 1:8 would be preferred.

...the longer barrels "generally" produce greater muzzle velosities and therefore greater rotational speed for any given twist rate...up to a point...before "barrel drag" becomes a factor...a 1 / 7 or 1 / 6.5 twist rate coupled with a 24 to 26 inch barrel will work "relatively" well with the longer 80 to 100 grain .224 inch diameter lead projectiles...however...for your purposes i would go with a 1 / 8 twist rate...a twist rate faster than 1 / 8 out or a barrel longer than 18 / 20 inches may be too fast for the 75 / 77 grain projectiles...especially in hot...humid...thin air...

 

[SkyPup]

Thank you very much, Ullie.

One thing is for absolute certain, I tend to have allot of hot humid air here in the armpit of Florida! :wink:

 

[SkyPup]

Well, bad news about the custom T/C barrel....

"At this time we do not offer twists other than what has been set by Thompson Center. The .223 would have the 1-12" twist."

 

[Gremlin]

This is what you want I think....

http://www.matchgrademachine.com/gunsho ... 287&page=1

 

[SkyPup]

WOW - thanks so much for that link. I am going to talk to them too! :wink:

 

[SkyPup]

This is what you want I think....

http://www.matchgrademachine.com/gunsho ... 287&page=1

Thanks so much for that excellent link, that is exactly what I want.

I ordered a 20" barrel with 1:8" twist drilled and tapped with a scope base.

Next up will be a real nice scope and set of rings!!! :lol:

 

[Gremlin]

Great! Let us know how she shoots!!

What scope are you going for?

I found TPS rings to be very nicely made (http://www.tpsproducts.com/)

 

[SkyPup]

I have not settled on a scope as of yet but I want this to be both a long range target rifle as well as a hunting rifle, so probably a variable scope is in order.

One of my friends has a Thompson Center Encore rifle with the 6.5mm SPC cartridge 20" barrel and a Leopold 3-9X scope for deer hunting and he really likes it, a super accurate light rifle.

 

[sigdizzy]

skypup, dang sorry I missed your posts by a day. TC does not make their barrels but orders them from someone, learned that today when talking to the TC rep, but dang can't remember who he said makes them. Who knows may be encore?? Let me know how it shoots. needing to tryout the r55 all weather LR when it warms up here and the little fur balls start poking their heads out of holes.

 

[SkyPup]

It is a custom Shilen barrel and takes 4-5 weeks until ready to ship.

Should be very accurate. Can't wait to get it!

http://www.shilen.com/calibersAndTwists.html

 

[SkyPup]

Since this is a hunting and target practice rifle, I am going to put the new Redfield Revolution 3-9X with 50mm objective and the Accu-Range reticle on it.


http://www.opticsplanet.net/redfiel...e-matte-finish-4-plex-accu-range-reticle.html

http://www.redfield.com/_media/downloads/Revolution_3-9x50mm.pdf

 

[SkyPup]

Welp, after two months of waiting on my custom 5.56mm barrel, I finally just received notification of its UPS shipment!!!

Yahoo!

 

[SkyPup]

The good man from UPS showed up right when I got home from work to deliver my custom Match Grade Machine Thompson Center Contender barrel in .223 Remington with a 20" crowned barrel and a 1:7" twist rate.

After I fed all the horses and dogs, I got right to work setting up the new rifle accouterments.

I mounted a new Redfield Revolution 3X9-50mm scope on a set of Burris XTR Low Mount rings in the custom MGM made base rail and took her out back to try her on the target range @ 50 yards using my handloaded 75 grain Hornady OTM shells.

Took the scope out back and put in a Cabelas .223 laser shell and zeroed the scope again the red laser dot on the side of my barn @ 50 yards.

First three shots out of the new barrel on the backyard target range were in a tight group right below and to the left of the bullseye. Next three were on the right of the bullseye and the final three before it got too dark to shoot were in a 1/2" group about 1/2" dead center above the bullsye! :lol:

No evidence of keyholing and the rifle handles the handloads for the SIG 556s real nice! :lol:

Pics of the finished rifle and 100 yard targets to follow later this week when I get a chance to wring her out with a couple dozen handloads!!! 8)

 

[SkyPup]

Here is the new OTM tack driver!!! 8)

Extremely light and accurate.

 

[Clyde]

SkyPup:

Man, that rifle and scope combo is really nice. 8) In fact, it is almost as nice as your log cabin, but I think at the end of the day the cabin wins the grand prize!

Nice wood grain on both of them, too, BTW!

Clyde

 

[ullie]

I ordered a 20" barrel with 1:8" twist drilled and tapped with a scope base.

The good man from UPS showed up right when I got home from work to deliver my custom Match Grade Machine Thompson Center Contender barrel in .223 Remington with a 20" crowned barrel and a 1:7" twist rate.

...hey SkyPup

...did you finally end up with a barrel in 1/8 or 1/7...just curious...

...BTW...very very nice !