I got a set of Dawson sights for my 320. They don't want to go in. Thankfully the slide is harder than the sights and I only marred the sight a little bit.

So some fitting has to be done. I've never had to fit a set, only used the pusher to do simple swaps.

How do I tell which side needs material removed? The rear went part in without force and just nosedived when I put some pressure on it. The front never wanted to seat into the dovetail and also tried to twist on me.

I have some files small enough to fit in there, I just can't really tell which way to go - a few passes on all 3 faces, or one specifically?

I was always of the understanding that you file the sight not the slide. Maybe that philosophy has changed(?).

Take the material off the bottom of the sight. Use a flat plate with emery paper or a fine file. Go slow until the sight goes at least 1/3 of the way in.

In fairness I've had to file and enlarge a damaged dovetail before but yes if nothings wrong with the gun then the sight gets filed. Just go slow and think through what you need to remove. Once you get close I've had luck dropping some oil in the dovetail in conjunction with the sight pusher. YMMV of course but it has worked for me.

Don't use a file on the dovetail of a 320. The dovetail is slightly different - it has a .001" tall bump in the middle - the sight should be fit so you can press it 1/3 of the way in with your fingers. Then use the pusher or brass punch to get it centered up.

When you have a dovetail this small, .003" variance will go from sloppy loose to hammer tight.

Listen to Dave Dawson. He has vids for front and rear sight fitting:

https://dawsonprecision.com/video-archive/

I've installed his sights on my Glocks and done Heinie's on my P320's, P239, P226 and P229. All it takes is understanding the basics and patience. Go slow. My preference is hammer and punch rather than sight pushers. More versatile and less expensive. However, gonna need a heavy bench vise and a solid bench.

I can offer nothing here as I’m too anal retentive and always have a respected smith put them on and measure them.

quote:

Originally posted by az4783054:
I was always of the understanding that you file the sight not the slide. Maybe that philosophy has changed(?).

Yes, going to be filing the sight. The male (?) dovetail on the sights have overhangs that would prevent a larger file for getting the full face.

quote:

Originally posted by MaSigchist:
Take the material off the bottom of the sight. Use a flat plate with emery paper or a fine file. Go slow until the sight goes at least 1/3 of the way in.

quote:

Originally posted by MaSigchist:
Don't use a file on the dovetail of a 320. The dovetail is slightly different - it has a .001" tall bump in the middle - the sight should be fit so you can press it 1/3 of the way in with your fingers. Then use the pusher or brass punch to get it centered up.

When you have a dovetail this small, .003" variance will go from sloppy loose to hammer tight.

Ah, perfect. I was thinking the bottom needed to be left alone to maintain the overall height of the sight.

I just need to clean up the burr that was raised when I tried to push too hard, then a pass at a time until I get it to slip in.

I though the stock set came out a bit easy on the follow-through. Makes sense.

No expert, but removed and replaced many sights on guns over the years using punches, never used a sight pusher.

At first I used lighter hammers, but learned heavier hammers imparted more force.

I have found aluminum punches do not mar the sights as much as other types, eg, brass, steel.
The best I have used are simple key stock in different sizes and lengths. Match them to the width of your sight, they are cheap , buy many, always keep them squared on the end you are using.

Sights are removed and installed in each manufacturers pattern. Try to find out prior to begiining work.

Fitting should be done on the sight , unless you are dressing up a damaged dovetail. Go slow removing metal.

And last, mistakes happen, along with damage, but never be in a rush, or work while frustrated. Give it a break, come back with a fresh mind.

Just my experiences.