# Rear sight replacement



## Dave H (Dec 19, 2018)

Has anyone used dry ice to cool the dovetail so I won't have to use a drift punch to install the adjustable rear sight? I know that thermal reduction is used to fit interference bearing races into axle tube station. Thoughts please.


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## desertman (Aug 29, 2013)

You didn't mention the what model gun it is? If you don't want to use a brass drift punch, you're probably gonna' need a sight installation tool. I don't see how you can use dry ice and only cool the sight without cooling the rest of the slide?


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## Steve M1911A1 (Feb 6, 2008)

Use a brass drift punch, and a rubber or plastic mallet (in case it slips).

Your pistol may be "full race," but it isn't a car.


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## Dave H (Dec 19, 2018)

desertman said:


> You didn't mention the what model gun it is? If you don't want to use a brass drift punch, you're probably gonna' need a sight installation tool. I don't see how you can use dry ice and only cool the sight without cooling the rest of the slide?


Its a Beretta 92 fs, 9 mm. The existing sight can't ulitize the thermal expansion method but the new one can. There is a you tube video showing their way of doing things on sight removal. My thought was to place the sight dovetail on the dry ice for a few minutes while I heat the disassembled slide with a heat gun (or hair dryer) to ulitize thermal expansion technique. A person would only need to heat the dovetail area of the slide. Hopefully this will allow an easier time to slide the new sight in place without filing or grinding the dovetail.


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## desertman (Aug 29, 2013)

Dave H said:


> Its a Beretta 92 fs, 9 mm. The existing sight can't ulitize the thermal expansion method but the new one can. There is a you tube video showing their way of doing things on sight removal. My thought was to place the sight dovetail on the dry ice for a few minutes while I heat the disassembled slide with a heat gun (or hair dryer) to ulitize thermal expansion technique. A person would only need to heat the dovetail area of the slide. Hopefully this will allow an easier time to slide the new sight in place without filing or grinding the dovetail.


I have a Model 92 FS. I suppose that method would work, depending on how tight the new sight is? But drifting out the old sight and installing a new one with a brass punch is no big deal. I would try that first. Unless of course the manufacturer of the replacement sight has specific instructions not to do so. In fact it's very common to make sight adjustments that way. Using a brass punch against steel won't mar it up as the brass is a lot softer than the steel. Just place the slide in a padded vise and gently tap the old one out and tap the new one in. A drop or two of penetrating oil may help. I've done this on a lot of guns before without any issues. I own a wide variety of different guns, eventually I bought a universal sight puller/installer. Obviously this makes no sense if you only have a few guns and probably wouldn't use it that often.

U Tube video's can be very helpful and informative. But you have to keep in mind that some of them are not so great and can do more harm than good. I've seen some people do some pretty dumb things to their guns while taking them apart and putting them back together on U Tube.


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## Dave H (Dec 19, 2018)

Absolutely correct on youtube, brass or bronze drifts. When I get my new adjustable rear sight, I'll see how it goes tapping out without using the brass drift and go from there. If I feel the need to use thermal expansion/contraction it will be after the lubrication step. Thanks for your assistance and I'll update when I finish. Take care and Merry Christmas!!


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## Dave H (Dec 19, 2018)

Oops, WITH not without.


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## desertman (Aug 29, 2013)

Dave H said:


> Absolutely correct on youtube, brass or bronze drifts. When I get my new adjustable rear sight, I'll see how it goes tapping out without using the brass drift and go from there. If I feel the need to use thermal expansion/contraction it will be after the lubrication step. Thanks for your assistance and I'll update when I finish. Take care and Merry Christmas!!


You're welcome! It's alway better to try the least complicated way first. If it gives you any trouble then try Plan B. Merry Christmas to you too.


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## denner12 (Oct 14, 2017)

I'd take it to a gunsmith and for about 20.00 bucks they should be able to install it properly.


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## SamBond (Aug 30, 2016)

I had a rear sight that I had to 'work' both directions to finally get it to budge, then I could move it.


Sam


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## Shipwreck (Jan 26, 2006)

SamBond said:


> I had a rear sight that I had to 'work' both directions to finally get it to budge, then I could move it.
> 
> Sam


Beretta rear sights are supposed to go in and out in a particular direction. I would not knock it from both sides - ya might damage the dovetail


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## Dave H (Dec 19, 2018)

Thanks guys, I got my sight today and used a brass pin to drive the old sight out. I was also super careful to support the slide where the dovetail was. I cut a notch out of some particle board strips out to fit around the safety de cocker lever. I also used some 3 in 1 oil as a lubricant. I didn't need to reef down on tge vice to hold it firm. Just snug. The first thing I noticed was the new dovetail was a wider than the base of the slide. I just split the difference on both sides. I tapped lightly to start the dovetail in its grove then used the brass pin. Be sure to back out the center set screw or you will mess up the threads. I have a small ball pein hammer to use and it went in fairly easily. Again thanks for your suggestions and MERRY CHRISTMAS!


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## Steve M1911A1 (Feb 6, 2008)

I'm glad that it went well.


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## Dave H (Dec 19, 2018)

Shipwreck said:


> Beretta rear sights are supposed to go in and out in a particular direction. I would not knock it from both sides - ya might damage the dovetail


Thanks for the info. My Beretta had a flare machined in on both sides. I was afraid to slide the sight in on the left for fear of hitting the de cocker lever. It went in just fine.


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## berettatoter (Sep 1, 2011)

And it's another home gunsmith job, done successfully!


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## Rock185 (Oct 26, 2012)

I have replaced quite a few dovetailed sights. Some required considerable fitting. I only wish I'd thought of dry ice!


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## Steve M1911A1 (Feb 6, 2008)

When I was confronted by a difficult, puzzling gunsmithing job, I would always think of ice.
The shot of Bourbon helped, too.


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## GeneralGeorge (Jul 11, 2020)

I have a 92FS with fixed rear site and want to install an adjustable site. Never done it before. This discussion is good but I have a couple of questions. Exactly what is a brass drift punch. I know what an ordinary steel punch is but haven't heard of the drift part. Would a store like Lowe's or Ace have one. Do I punch out from right to left and left to right to install new one. Thanks. What size punch would I need. Should the decocker be removed.


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## rustygun (Apr 8, 2013)

A brass drift punch can be as simple as a round piece of solid brass or anything that is softer than steel and won't mar any finishes that you can hold against the site and tap other end with hammer . I have a piece of solid copper about 3/8" around and 3-4 inches long that works great.


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## Soarin1 (Jun 6, 2020)

GeneralGeorge said:


> I have a 92FS with fixed rear site and want to install an adjustable site. Never done it before. This discussion is good but I have a couple of questions. Exactly what is a brass drift punch. I know what an ordinary steel punch is but haven't heard of the drift part. Would a store like Lowe's or Ace have one. Do I punch out from right to left and left to right to install new one. Thanks. What size punch would I need. Should the decocker be removed.


Follow advice for good brass punch, don't buy the junk from Lowes, etc. Order a good set for around $50 from Brownell etc. You can always use some heat carefully, then penetrating oil like Wd40. Old school, give it good whack 1st after few minutes. Or, ante up & buy a sight presser.

Sent from my SM-G973U using Tapatalk


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