Installing sights question

[user 52142]

Building a Pedersoli PK3315, Scout Carbine, percussion, 50 cal. Will be finishing up bluing the barrel and installing the sights this weekend.

I beleive you install left to right. But curious how you get them centered on the barrel.

I know you cant get them perfect and will need to adjust with a brass drift at the range. But want to at least be on the paper.....

 

[FishDFly]

Eye ball it or measure with calipers, should be equal distance on each side of the barrel.

Shoot at 12 1/2 yards on paper to start.

 

[user 52142]

Thanks FishDFly. That's what I was thinking, but wanted some wisdom and advice from the experts.

 

[andy52]

To start I just generally eyeball them and work from there at the range.

 

[FishDFly]

Eye will get them centered.

 

[Larry (Omaha)]

Building a Pedersoli PK3315, Scout Carbine, percussion, 50 cal. Will be finishing up bluing the barrel and installing the sights this weekend.

I beleive you install left to right. But curious how you get them centered on the barrel.

I know you cant get them perfect and will need to adjust with a brass drift at the range. But want to at least be on the paper.....

I personally do not know anything about your gun. If the dovetail has already been milled in the barrel and tapered, then the sight will have to go accordingly. Determine which end of the barrel dovetail is the largest and that is where to start.
Eyeball center is good!
Larry

 

[user 52142]

Great big THANK YOU to everyone. I really appreciate you sharing your knowledge

 

[Phil Coffins]

Dovetails and sights are machine made and are straight. Start on the side that suits you and the human eye will allow you to get them well centered. Hand filed dovetails often have a taper due to lack of care by the filer.

 

[Larry (Omaha)]

Eye ball it or measure with calipers, should be equal distance on each side of the barrel.

Shoot at 12 1/2 yards on paper to start.

This is a new one on me. What is the reason behind such a short distance? I was alway taught (which doesn't mean I am correct) that a group needs to be worked up first, then adjust sights. A short distance can't possibly determine a decent group. Help me out here.
Thanks
Larry

 

[FishDFly]

At 12 1/2 yards, it is hard to miss the target.

The 12 1/2 comes from reading here over the years as the place to start with a rifle. If it is close back up to 25.

 

[Dude]

I've always heard that pins and dovetailed things go in from the right and exit the right. Just yesterday I removed the Renegade front sight, and after measuring its width determined it was slightly tapered about .020 and needed to enter from the right side.

I've used a bore sight to get the sights roughly aligned.

 

[user 52142]

Good advice Dude, Thanks

 

[Phil Coffins]

A dove tail with .020” of taper in .500” would have be a 2.29 degree taper. In that case a sight that was tight would fall out if tapped slightly back. Having removed many sights I’ve yet to have one come loose till it was well on the way out of a dove tail. And if you had that much taper taking a sight out for say refinish would mean that it would be easy to start by hand then not get tight till it went past were it should be.

 

[Dude]

You could be right, Phil. I didn't look close at the caliper and was guessing when I said that. I couldn't remember if it was .010 or .020. It might have been .010, but don't think it was less than that. I could knock it back out and get back with the measurement.

 

[Old Hawkeye]

Dovetails and sights are machine made and are straight. Start on the side that suits you and the human eye will allow you to get them well centered. Hand filed dovetails often have a taper due to lack of care by the filer.

WRONG! Dovetails in the barrel are machined straight, but the male dovetail on sights are machined with a taper and should be installed from the right side. If you don't you will have major problems fitting them. You can actually see the taper in the sight dovetails if you look closely. Most sight dovetails need to be filed & fitted to the barrel dovetail, as the barrel dovetail can vary several thousandths. 3/8" dovetails cut in barrels can be from .359 to .370 in most cases, but sight dovetails will be fairly close to .375" & the taper can make them even wider. Just my experience from having installed several hundred of them.

 

[HiDesertHunter]

WRONG! Dovetails in the barrel are machined straight, but the male dovetail on sights are machined with a taper and should be installed from the right side.

This is correct!

Also a good way to 'fit' the sight dovetail is to use a bench stone with oil and 'stone' the base of the sight dovetail on the flat of the stone by sliding it back and forth on the stone. Do this a little at a time and when you can slide the sight in about a 1/3 of the way by 'hand' you are ready to 'drift' it in the rest of the way.

 

[Dude]

That sounds like excellent advice, HDHunter! Thank you! I've copied it to my notebook.

 

[HiDesertHunter]

That sounds like excellent advice, HDHunter! Thank you! I've copied it to my notebook.

Yea filing is inconsistent and can result in the base not being level, or removing too much metal.

The stone removes very little and keeps the base flat & level!

 

[Phil Coffins]

I’m always interested in learning and having installed sights on many types of firearms and can confirm the barrel dovetail is machined straight. Just now I measured several male dovetails on new sights. Some are cast most are machined. These include Lyman, Marbles, Glock. Shiloh and Williams. The largest variation I found was .003” in the width.

 

[user 52142]

Thanks for all of the great information. I think I will get my calipers out and check