KCSO
11-28-2007, 12:15 PM
I thought Ii would share this as i have had this problem show up in both Puma and Taurus and Uberti rifles in 45 Colt.
Your new gun will shoot 3 shots or less fine and then the more you shoot the more the accuracy falls off, or the gun just won't hold a group. Or more importantly for us accuracy with lead bulets is so-so and jacketed slugs seem to shoot fine.
Clean the bore and then inspect the bore with a bright light or bore scope. Likely you will find a small dent or hump inside the bore where the front sight is dovetailed in. What happens is that in 45 colt the bore is very thin under the dovetails and if they use a press to put in the sights they can actually wrinkle or dent the bore under the front sight. The only cure is to cut the barrel back and carefully dovetail in a new sight. I just finished taking a Thunderbolt back to a 24" barrel to cure this problem and the rifle went from 3" groups at 50 yards to 1 1/2" and the gun will now group jacketed and lead to the same p.o.a.
When cutting a dovetail on a 45 colt barrel just a few thou. is the difference between being able to install the sight right and wrinkling the tube.
Your new gun will shoot 3 shots or less fine and then the more you shoot the more the accuracy falls off, or the gun just won't hold a group. Or more importantly for us accuracy with lead bulets is so-so and jacketed slugs seem to shoot fine.
Clean the bore and then inspect the bore with a bright light or bore scope. Likely you will find a small dent or hump inside the bore where the front sight is dovetailed in. What happens is that in 45 colt the bore is very thin under the dovetails and if they use a press to put in the sights they can actually wrinkle or dent the bore under the front sight. The only cure is to cut the barrel back and carefully dovetail in a new sight. I just finished taking a Thunderbolt back to a 24" barrel to cure this problem and the rifle went from 3" groups at 50 yards to 1 1/2" and the gun will now group jacketed and lead to the same p.o.a.
When cutting a dovetail on a 45 colt barrel just a few thou. is the difference between being able to install the sight right and wrinkling the tube.