Uberti Model '66 accuracy

[JohnnyB]

I have a Uberti 1866 Winchester replica in .45 Colt with a 24.25" barrel. My best load for that rifle seems to be 10.5 gr of HS-6 with a 250 gr RNFP hard cast lead bullet. I finish each round off with Lee Factory Crimp die. That load seems to group no better than 3.5" to 4.5" group @ 50yds. At 25 yds, it shoots about 1 - 1.25" groups all day long. I am wondering if maybe a lighter bullet ( or maybe even heavier) would group better. Could it be that since that a .45 Colt was originally meant for revolvers, that in a rifle, it loses something? It's a beautiful rifle, I just wish that it was more accurate.
Any opinions? Ideas?

 

[eastbank]

try a jacketed bullet,i use the 225gr hornady and 250gr, i use them in a 1892 win repo at 1100-1200 fps. eastbank.

 

[Tommygunn]

I have a Browning B-92 in .44MAGNUM. I once found some UMC .44 SP that were cast bullets and after a few rounds all I got were really wild flyers -- they wouldn't even hit the target paper!!! When I got home and cleaned the rifle it was horrible; ~~ the action was full of powdered lead, like talcum powder. I have never spent so much time & effort cleaning out a weapon's barrel & action!
I tossed the remainer of that box, never to go back to cast lead bullets be it Magnum or special.
Whether your problem is this, I don't know. I have a Uberti 1873 in .44-40 that seems happy enough with either jacketed rounds or plain lead rounds loaded with blackpowder.


But it's worth a try.

 

[Onmilo]

Try Unique powder, 7.5 grains under that bullet.
HS-6 is a bit too fast burning for that long barrel.

 

[GooseGestapo]

A lot of bad/misinformation so far.
HS-6 is actually SLOWER than Unique.

I'm not familiar with the Uberti 66, but I'm familiar with the .45Colt in handgun and long-guns.
My cast bullets shoot well, but not quite as good as a first quality jacketed bullet.
Good cast bullets DON'T lead. The leading issue by the poster above is with SWAGED lead bullets that indeed can cause extreme leading when used with heavy charges of powder that push them too fast.

HS-6 has a stellar reputation for accuracy in the .45LC. I personally use Hod. LongShot which is very similar in burn rate. Ditto Universal and Unique which have similar burn rates, but faster than HS-6 or LongShot.

I suggest you try a bullet of larger diameter than the typical .452" of lead/cast bullets. Frequently a bullet from another manufacturer will give better accuracy.

I use my own cast bullets and get ~2" groups at 50yds from my Winchester Mod94 "Legacy" w/24" bbl.
With a charge of 19.8gr of #2400 under a 250gr Hornady XTP (Jacketed Hollow Point) I get occasional 1.5" groups at 100yds. (warning; this load for modern/strong actions only: use at your own risk... Nosler published load for Ruger revolvers).
It really "pisses" off some scoped bolt-action rifle shooters to see the "old winchester" with a reciever sight shoot that good...

 

[BCRider]

I'm not familiar with HS-6 enough to know if this is a heavy or light charge. But consider that ANY load that stays within the modest pressure limits for .45Colt just might have a hard time obturating a harder bullet out for a good fit and seal in the bore. So I'd suggest that you start by slugging the bore with a soft lead ball beaten in with a wood or plastic mallet and measure the groove and land diameters. It really helps with selecting a bullet for diameter for the best results.

With a softer bullet the modest pressure would tend to bump out the lead and ensure a good seal and good lock to the rifling. But depending on just how hard your bullets are and their size you may not be getting this. It may be that you need to go to a softer lead to let it obturate out more fully or start with a bullet that is a thou or two larger than the groove diameter and let the pressure swage fit it to the bore as it enters the leade of the chamber and on into the rifling. Either way though from all I've read you want a good seal with cast bullets or you're going to get blow by that tends to reduce consistency and can often produce leading in the bore.

Jacketed bullets don't seem as fussy about all this as cast lead. Perhaps start with a few .452 jacketed and see if there's an improvement.