Uberti NWMP accuracy issues

[will52100]

Got a couple accuracy issues with my Cimmeron NWMP.  It's a Uberti in 45-75.

Biggest issue is that it's shooting 3' high at a 100 yards with a 350 grain bullet and 69 grains of 2f swiss powder.

Smokeless was 2 1/2' high at same distance.

Looked close to a 12" group as well with both loadings.  Now some of that might be me firing off the bead rail of my truck, but I've gotten 1 moa from my m14 doing that as well.  Some might be the less than target quality sights, but I would have expected 3-4" groups or better from the way I was shooting and the sight picture I got.

Now there's two options I can think of to fix it.  One is to lengthen the front sight, and since it is a dove tail I will attempt to knock it out and mill a slot and add a longer blade.

The other I'm concerned about is the mag tube.  That sucker is in there tight!  I had to prize it out, and thought I was going to destroy the hand guard doing that.  I'm wondering if since it's so tight if that may be flexing the barrel up, causing some of the overshooting issues, and if the heavy tension is also causing some of the "shot gun" pattern I'm getting.  If I do trim the end down, how tight or loose should it fit?  I'm thinking since it's captured by the frame and nose cap that just a few thousandths of movement fore and aft should be about rite, a little wiggle if you will.

Thanks

[larryo_1]

Will, my guess would be to change sights first off and also concerning that mag tube, it does sound as though it is in there too tight.  When I took my rifle apart to redo the wood, my mag tube came out pretty good so perhaps a bit of metal removal inside the fore end cap and also the tube ring might help but don't carried away there.  If you were to do this you should do it a bit at a time and just enough to allow the tube to slide sort of free but not sloppy if you get the drift.  With these rifles, tho, I doubt that barrel whip is much of a problem.  Probably just using sandpaper on the insides would be enough  but that is IMHO.

[will52100]

Thanks.  I took nearly 1/16" off the end of the tube to free it up, didn't cure all the issues but I went from 36" high at 100 yards to 20" high.  What I can't figure out is how they got it on in the first place, didn't see where it'd been hit with a 10 pound hammer.

I took the front sight out and cut a slot in it and silver brazed a flat piece of 1084, got it pretty well dialed in now.  The rear is very well made, but it's very open windage wise, good for close hunting and fast targets, not so good for paper.