An interesting discovery when shooting my MkIII

[rayg]

In shooting cast bullets in my Mk III, PLY stamped rifle I posted about earlier. The rifle was shooting way left and rear sight was at it's maximin to the right and still would not bring the bullet to the right to correct the problem.

I had not fired imilitary ammo in it yet as I generally only fire cast bullets in my military rifles and it dawned on me that maybe barrel harmonics might be playing a role in the issue.
All my other military rifles, except one, fired point of bore sight with cast bullets so I figured that harmonics might be impacting the Ross rifle and I took some military rds to the range the next time and fired them and the rifle fired point of bore sight like it is supposed to.
All my other military rifles fired point of bore sight with cast bullets but one.
I had a MkII*** Ross that fired point of bore sight with cast bullets so apparently the Ross III barrel is heavier or stiffer and the light cast loads would not flex the barrel correctly.
Ray

Information

Warning: This is a relatively older thread This discussion is older than 360 days. Some information contained in it may no longer be current.

[jmoore]

Not unlike the recent thread on the French Berthier carbine that shot to one side with cast bullets, except the carbine had the noticable offset built into the fixed front sight to compensate for full power loads.

[rayg]

Not unlike the recent thread on the French Berthier carbine that shot to one side with cast bullets, except the carbine had the noticable offset built into the fixed front sight to compensate for full power loads.

Yes that was mine and the exception I mentioned. The thin barrel of that carbine was apparently tuned for flex for full power loads, Ray

[bushwhacker]

Speaking of offset front sights, I sold a MKIII that had a noticeable twist to the side of the front sight assembly. Had to come from the factory that way as it was a full length barrel. The only way I could see it could be fixed was to pull the sight assembly and re-install it in correct position and then use a tapered reamer to oversize and align the pin hole. Don't know if the buyer ever did that. I never noticed until he sent me back a photol

[jmoore]

Speaking of offset front sights...

In the case of the French Carbines, it was quite intentional. And rather noticeable!:

[smellie]

Originally the barrel of the Ross Mark III was 30.5 inches and very heavy.

If you take one apart, you will notice that the action, apart from the actual lockup area, is very lightweight construction; all the weight of the rifle was in that barrel.

Most of the PLYmouth RMLI rifles in circulation have had their barrels cut back to 24 or 26 inches. This would DEFINITELY upset the original vibration pattern.

Hope this helps.