25-5 throats and how to check them before buying one

Gun 4 Fun

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There's been a few threads here again lately about the model 25-5. Rather than post this in someone else's thread and veer it too far off course, I thought it might be helpful to many if I posted this again. I have been away from this forum for a while, but I used to post this here regularly when members would start asking about this subject. The following may also be of benefit to potential buyers of 25-2's since many of them suffered from the same factory flaw of having over sized throats.


For the record, there were a few model 25's with the N serial prefix that were built at the end of that serial number system's range that were produced with the proper throats as S&W was starting to listen to their customers and had started to tighten up their specs (though in the case of the 25-2, the throats varied from correct, to as bad as the early 25-5's were all throughout its production life for some reason). Finding a 25-5 that has a pinned barrel that has the potential to be a good shooter is generally a matter of luck, but knowing how to check them prior to buying can be helpful if you are looking for a shooter more than a one for your collection.


The following may help many of you-

The older Pinned guns with the N prefix had over-sized throats and were not the best shooters. Some with a N prefix did have the correct throats, but they are the exception to the rule, as most will be .455"-.458" in diameter. Any 25-5 with the ABC 1234 serial system will have the correct throats in it and should be a great shooter ( as long as it has been taken care of, of course). All 25-7's and later guns will also have the proper throats.

To check the throats, take a jacketed bullet (use a jacketed bullet and not lead, since lead is normally lubed and sticky in and of its own nature anyway, which can give a false impression that they are fitting correctly) with you (Hornady 300 gr XTP's work best because they are longer and are .452" in diameter) and drop it into the chamber from the rear. If it falls right on through, the throats are too large ( normally .455" or bigger) to give very good accuracy with standard .45 Colt bullets that run .451"-.452". If it hangs up briefly in the throat, then falls on out, you are looking at throats that will be in the area of .453"- .454", and will work with some of the larger bullets out like the factory Win, and Rem swaged lead bullets, and may work fairly well with standard diameter .45 caliber bullets.

If it hangs up in the throat, but can be pushed on through using a pencil or pen, and using only finger pressure to do so, you have a gun that will potentially be very accurate and what you are looking for in a shooter.

If you get one that has large throats, the Winchester and Remington swaged lead bullets that they sell at places like Cabela's will usually improve their accuracy with standard loads by quite a bit since they run .456" and .455"respectively, and have hollow bases to help the bullets obturate and fill the throats which in turn help align them with the bore before entering the forcing cone.
 
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You've described the situation fairly well, as far as my experience indicates. Now if you can come up with a fix for all the N-frame .45 Colts that shoot terribly high and that have an integral front blade (cannot readily be replaced) you would really have something more to write about! My Model 25-9 only shoots about 8-inches high at 25-yards with every 250-gr load I have tried in it. I wonder if it was intended for 300-yard shooting? :)
 
You've described the situation fairly well, as far as my experience indicates. Now if you can come up with a fix for all the N-frame .45 Colts that shoot terribly high and that have an integral front blade (cannot readily be replaced) you would really have something more to write about! My Model 25-9 only shoots about 8-inches high at 25-yards with every 250-gr load I have tried in it. I wonder if it was intended for 300-yard shooting? :)

Got ya covered there too.:D

Call S&W and order the .106" rear sight blade. I actually filed my own down and touched it up with cold blue (that has lasted very well so far) before I ever thought about calling them, but once I did call, they sent me the new blade and the attaching screw and new nut.

Turned out I had my filed my original blade to the same height, so I still have my white outline blade. It is bottomed out still, but at least it hits to point of aim at 25 yards with any load I have tried in the years since.
 
There are some casters offering bullets in the 454-455 and maybe larger sizes including penn and chey-cast.

Thanks for posting. I knew some were starting to do that to help out guys with guns that have over-sized throats, especially some of the cowboy action shooters.

The problem is that many, many S&W's (and many Colts as well), have throats that are running at .456"-.458". If these larger cast bullets are too hard, which many of them are to ease production, they won't obturate properly in the throats, so accuracy is still iffy most of the time. Now, if these some of these guys will start offering their cast bullets at 10 or so BHN, that would really help.

Edited to add:
Many of the newer and larger bullets that are starting to show up are doing so directly because of threads like the ones here on this forum, and on other boards as well where guys have been complaining about this issue for so long. It's nice to know that casters are stepping up to help. It at least makes it possible to shoot a gun with over-sized throats a lot more accurately. If a guy wants to shoot jacketed bullets only though, he's still out of luck if he has a gun with the large throats.
 
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I installed a .126 blade on my gun because it was the lowest I had. That got me to the 8-inches high figure. :rolleyes:

It's a 4-inch gun. I doubt the .020-lower will cure it, but let me do some calculations. I did not realize S&W made a .106 blade for the K- & N-frames. I think one of those on an N-frame would have to present the proverbial "sight picture from..." (where Mephisto calls from).
 
The smartest thing a guy can do before buying a gun in 45 colt is to put a few pin gauges or bullets in his pocket and check those throats.Thats a bad feeling to spend money on a gun only to find it doesn't shoot.
 
Mine is a 4" gun as well. They came stock with a .126" blade. The .106 made a big enough difference that I could finally get to zero at 25 yards.
 
Gun 4 Fun;
This a really helpful post for those that may have not understood the potential problems with these revolvers.

Being a "certified old fart" I started with Smith in the early fifties (my father was a real "gunny" and we shot together when I was very young). He was a tool maker and started me casting bullets when I was about fourteen. Since he was a precision machinist he early on understood the mechanical side (problems and solutions) and I got a VERY early understanding of these problems.

When the dimensions on a revolver are correct it is amazing the accuracy that is possible. When they are not, well...(:>().

Dale53
 
What about 25-2's?

Do these tend to have the same problems?

I just bought one with a serial number starting with N dating to around 1978.

Maybe when I finally buy a 45 Colt I'll go for a Ruger Blackhawk.

45 Colt seems like a round that calls for a single action anyway given it's old west roots. :)

Dave
 
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We should mention that the Colt SAA also has this problem with over sized throats.Mine is a 5 year old 3rd generation gun and .454 diameter bullets are just the ticket..452 factory loads were a bit disappointing...
 
We should mention that the Colt SAA also has this problem with over sized throats.Mine is a 5 year old 3rd generation gun and .454 diameter bullets are just the ticket..452 factory loads were a bit disappointing...

I mentioned the Colts in my OP, though I didn't go into detail since most guys here are asking about the 25's.;)
 
What about 25-2's?

Do these tend to have the same problems?

I just bought one with a serial number starting with N dating to around 1978.

Maybe when I finally buy a 45 Colt I'll go for a Ruger Blackhawk.

45 Colt seems like a round that calls for a single action anyway given it's old west roots. :)

Dave

Dave, the 25-2 have the same problem, though as I pointed out in my OP, they were all over the place throughout their production life. Many guys here have them that have correct throats, while others like me have have them that have over-sized throats. I got such a good deal on mine that I couldn't pass it up regardless of the throats. I am a long time handloader, so I knew how to make it shoot. Mine has throats that run .456" average, but vary slightly from chamber to chamber, which is far more common than most guys know.
 
A personal story on this topic:

Back in the 1970s I bought an early 25-5 with 4-inch barrel, and enjoyed shooting it a lot. For some reason I decided I wanted more velocity out of the .45 Colt, so I sold my gun and purchased a 6-inch 25-5. It wouldn't shoot worth a damn, and I was very frustrated with it and finally sold it. A few years later I had the chance to buy back my old 4-inch, and I did so. It still shot great. By this time (early to mid-80s) I knew enough to be aware of the issues with throats in the 25 series. I checked the throats on the 4-inch with a jacketed bullet as suggested above. In five chambers it required a sound tap with a cleaning rod to push the bullet through; in one chamber it required only the lightest touch to push it through. I never had the chance to do this test on the 6-inch, but I am guessing the bullet would have dropped through easily on all of them.

The 4-incher will not be for sale again during my lifetime, and I expect to live to at least 130.

Cheers,
Whisper
 
I think someone mentioned that the throat issue wasn't as big a problem with jacketed bullets.

Why is that? (or is it not true?)

Is it because jacketed bullets obturate more readily?
 
Jacketed bullets tend to grab and hold the rifling and not skid as readily when the bullet hits the bore at less than perfect alignment like lead bullets can and do, so they tend to shoot better than lead in guns with over-sized throats.
 
Jacketed bullets tend to grab and hold the rifling and not skid as readily when the bullet hits the bore at less than perfect alignment like lead bullets can and do, so they tend to shoot better than lead in guns with over-sized throats.

This may explain why 25-2's haven't developed as big a reputation for accuracy problems.

For people who shoot factory loads, lead bullets are fairly unusual in 45 acp but common for 45 colt.
 
Gun4Fun,
That is a great post summarizing bits of information in many posts about oversized throats. I wanted a 25-5 so I researched S&W Forum topics. When I recently found one with an AWF64XX serial number, it sealed the deal. The owner reported it was an accurate shooter and it is. The chamber throats measure .4525 inches by a pin gauge.
 
just pick up a 1980 25-5 and it shoots great!!!.....took a .452 SWC when i made the buy and the bullet went through with a slight push....just take a bullet with you and check it....
 
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