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meric35
January 17, 2011, 05:41 PM
I have (2) 1858 Remingtons a Pietta 44 and Uberti 36 I really like both of them however I have an issue with bullet drop on the 36.

I load the 44 with 28 grains Pyrodex P and can hit a target at 25 yard at almost point of aim, meaning the bullet has only about a 1" drop from where I aim.

However the Uberti 36 with a recommended max load of 20 grains of Pyrodex P has about an 8" drop at 25 yards. It is very accurate at 10 yards with no noticable drop. Should I increase the amount of powder I use in the 36 to reduce bullet drop or do the sights need to be "adjusted" (they are fixed sights)

The book says not to use more than 20 grain of Pyrodex though so I'm not sure if I should increase the amount.

mykeal
January 17, 2011, 06:51 PM
The Uberti can handle much more than 20, grains, and you'll probably get better groups with more powder. But the 8" drop is definitely sight alignment. There's no way a .375 or .380 round ball propelled by 20 grains of black powder drops 8" in 25 yards.

Frankly, I think your .44 needs sight work also. A 1" drop in 25 yards is also excessive.

You should be evaluating gun performance based on group center rather than individual round location. If your (minimum of 3 rounds each) groups are 1" below point of aim, then you have something you can work with.

kwhi43@kc.rr.com
January 17, 2011, 07:05 PM
I only shoot 17 grs in my .36 and there is no drop from 25yds and 50yds,
It hits dead on at 25 and the same at 50.

meric35
January 17, 2011, 08:13 PM
Grouping is always consistant with both guns. 3 shots normaly touch each other. Just low on both guns. The pietta has Target sights so I can adjust them easy.

I will try more powder in the uberti first. Maybe 24 grains?

How would I adjust fixed sight to raise the shot?

Thanks

robhof
January 17, 2011, 08:18 PM
File the top of the front sight; use a fine grit file and only a few strokes at a time then test fire, repeat til where you want, removing metal is easy, too much and you got a Smith's problem.:confused::mad:

napp
January 17, 2011, 08:30 PM
How would I adjust fixed sight to raise the shot?

To raise the bullet strike you must either make the rear sight higher or the front sight lower. With fixed sights, this is best accomplished by gradually and carefully removing metal from the top of the front sight with a file.

Remove a small amount and test fire. If needed, remove a small amount again and test fire again. Repeat this process until the sights align to your satisfaction. Then, use some cold blue to protect the raw metal where you filed.

The words in bold are key to this modification. You can't undo what the file has done.

Edit: Looks like robhof said it faster and more succinctly. :D

mykeal
January 18, 2011, 07:02 AM
You can calculate the amount necessary: reduce the height of the front sight (in inches) by the amount you want the POI to raise multiplied by the distance between the front and rear sights in inches, then divided by the distance to the target in inches.

That gives you an idea of the amount of filing necessary, but unless you're supremely confident in your ability to hit exactly where you're aiming (one ragged hole from 3 shots at 25 yards, for instance), do your filing in small steps as has already been advised.

meric35
January 18, 2011, 02:20 PM
You can calculate the amount necessary: reduce the height of the front sight (in inches) by the amount you want the POI to raise multiplied by the distance between the front and rear sights in inches, then divided by the distance to the target in inches.

Ouch, I was never any good at word problems. I think I'll try more powder first then if that don't work slowly file down the front sight. It is only 1.5" tall to start with.

Thanks for all the advice.

napp
January 18, 2011, 03:55 PM
I'm inclined to agree with what mykeal said in post #2. If you are sure you are consistently using correct sight alignment and sight picture, I seriously doubt that the answer lies in the powder charge. A drop of eight inches at 25 yards using a 20 grain charge is a bunch.:eek: