My 645 has the factory fixed sights. It shoots straight, but low if I center the Red Ramp in the White Outline. If I hold the front to where the bottom of the Red lines up with the top of the rear sight it hits dead on. The way I see it, I can have the front sight shaved or replace the rear with an adjustable. Any one have any recommendations as to what brand of sight to use and where to get one, and can I install it myself or should I have a smith do it? Thanx for any advice!

There's only one source I know of for an adjustable aftermarket rear sight... LPA. They make 3 versions for the 645, look for the TR64S* models.

MidwayUSA carries them, only the TR64SW30 (3-dot) model is in stock. The other 2 (white outline & plain) are out of stock, but backorder ok.

They are well made. I have them on my Glock G22 and a 1006.

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Conrad
SWCA #1830 SWHF #222

Pachmayr made an adjustable rear sight(the accuset sight system part number 06370) in the 90s for the 645. I just bought one for mine two weeks ago NOS on ebay, $60. Installed it myself, beautiful solution to my problem. I looked the lpa but everyone was out of stock on the white outline unit. pm me if you have any questions-bill

My 645 shoots dead on with the top of the front sight even with the top of the rear sight using 230 grains. Shooting a lighter grain bullet can shoot low. Hard to imagine but the heavier bullet spends more time inside the barrel so is more affected by muzzle rise during recoil. Jim.

Thanks for all the info! I went to Midway's site, the LPA seems to be the solution if I can't find an old Millett or Pachmayr (lucky guy!). Now here's another question: Since I've managed to misplace the "Owner's Manual" for the 645, if I drift the fixed sight out of the slide, do I have to worry about anything falling/popping/springing out? I seem to recall that when I took the adjustable sight on my 439 apart, that happened. Thanks again!

Google takes about 2 seconds to come up with a parts diagram for a 645 and there looks to be a spring or so which will pop out on sight removal.

Yes.... like all 2nd & 3rd gen pistols (and the M&P's too) there's a spring and plunger hiding underneath it waiting to go... boing!

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Conrad
SWCA #1830 SWHF #222

two springs and two plungers covered by a metal plate that sits under the rear sight. ba