sighting in

[drpepper]

I have a GPR 54 cal and having a lot of problems with it shooting to low, Raise the rear sight as high as it would go and still shoots low. Started with 50gr of fff powder. HELP

 

[Padraic]

There is a few things you could change like patch thickness ball diameter etc. See if changing one or both of those makes a difference. If not you could always file down the front sight a little bit at a time to raise point of impact. Good luck.

 

[Blizzard of '93]

If you are shooting PRB raise the charge up to an '06 caseful (about 70 grs.), if no help you can always file down/replace the front sight.

 

[Huntnut]

Is it a new gun? When I got mine I had to put 100-150rounds down it to get the barrel broke in and the it started shooting higher.

 

[AeroncaTAL]

I had the same problem with my GPR. The front sight on the Lyman is pretty big. I probably filed about a third of the sight down. Do it slowly, you don't want to take too much off...
Scott

 

[redwing]

You did not say at what range you were shooting? The .54 takes a lot of fuel to shoot well. I use 60 grs. at 25 Yds. 70 Grs. at 50yds. and 80 to 90 Grs at 100 yds depending on the wind. I shoot 3F Shuetzen in a flinter 43" 15/16s Getz flat bottom rifled, straight wall. :thumbsup:

 

[tg]

Most production guns with this type of sights need some filing to bring the POI up,,as mentioned just go slow, the best thing to do is find an accurate load then adjust for elevation.

 

[tx50cal]

It's also a good idea to set the rear sight about 1/2 way if adjustable. This way as you file the front you can fine tune with the rear.

 

[Zonie]

The Lyman GPR is intentionally built with the front sight too tall so that it can be filed down to suit the powder load, projectile type, and range that you want to shoot.

If it is a new gun, expect to have to file the front sight.
If it is a used gun expect to have to file the front sight because the previous owner didn't know about the tall front sight and he never could get it to hit dead center. That's why you got such a good deal on it. :grin:

When you take your flat file and shooting equipment to the range the next time, don't forget to lower your rear sight to about mid-height before you start filing.

For shooting at 50 yards, removing .012 from the front sight will raise the impact location 1 inch so, if it is hitting 6 inches low, you will need to remove 6 X .012 = .072 or slightly more than 1/16 of an inch.

If your shooting at 25 yards (which I recommend for the first sighting in) you will have to remove .024 from the sight to raise the point of impact 1 inch so, if it is hitting 6 inches low at 25 yards, you will have to remove 6 X .024 = .145 from the front sight. That is about 5/32 inch.

Use these numbers as rough guides and then use the rear sight adjustment to get it to hit right where you want it to hit.

Have Fun!! :grin:
zonie

 

[MFP308]

Ok so the filing is done and the front sight is where it should be, what do you do to fix the raw metal on the top of the sight? Reblue?

Mike

 

[Rebel]

Cold blue it.

 

[paulvallandigham]

Yes, re blue it. If you heat up the sight with a torch and then wipe it with cold blue while its hot, you will get a very dark blue color. Then spray it with oil to cool the metal back down to room temperature. The oil will help " cook " the bluing into the metal, and the blue will last much longer than simply applying cold blue " cold ".

 

[MFP308]

Rebel, Paul thank you. I was wondering about that for some time.


Mike

 

[tg]

I would also suggest putting the fixed rear sight on and get away from that adjustable one, they are not a very good sight.

 

[Dave K]

That is exactly what I did TG. Once you have a hunting load you like, you aren't going to change it anyhow. That factory adj. rear sight had too many variables in it for my taste.