Question is in the title. Always seemed a little redundant to me. I see both lengths are offered in the full size, 4" only in the compact. Will a 4.25" (or longer) barrel work on the compact frame? Thanks.

It's a Canadian thing.
Less than 4.25 not legal for import.
Don't know about swapping out barrels.

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George

Yep, some Canuck concluded that 4.25” barrels are less deadly and harder to conceal. Looks like there will be more 3” Pythons available for us Yankees.

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213th FBINA

If going from 4" to 4.25" so a gun would be harder to carry ... why not a 10" or 12" minimum length ... but the REAL reason is to limit the guns from makers in the USA ... a lot of makers aren't going to make two models of guns ...one just for the Canadian market .
It's all about limiting access to handguns ...NOT about .25" being safer or harder to conceal . That's just the excuse they spew out to the masses .
Who said " Americans are so gullible ! " Vladimir Putin and he is so right it isn't even funny !
Gary

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Certified Cajun
NRA Member

Quasi-humorous quips don't help answer the OP's question. Canada designates classes of firearms. Those with barrels less than 105 mm fall in to the prohibited bucket. This is 4.13" hence the 4.25" barrel length on some US firearms.

Classes of firearms | Royal Canadian Mounted Police

With the restrictions on handguns up there, how big could the Canadian market be?
What about all the Americans that have close-fitted leather holsters made for 4” barrels that won’t fit 4 1/4” barrels?

Soon, maybe now. All we will get is 4.25 in. barrels. They won't make 2 lengths......Checked the catalog specs lately?

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S&W Accumulator

Once upon a time, I was looking for a spare barrel for a Sig that was 3.9". I found a listing for one that said 106mm and wondered why? Found out about the Canadian restrictions.

Yes, i bought a 4” frame and put the 4.25” slide on it and it works fine.

I may be wrong but i think both those guns use the 4” lower from the factory.


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That's what I figured, thanks. Love the graphics. I bet a 4.25 barrel should work with a 4" slide as well.

Guess I'm still surprised they sell both here even if there's a good reason for the two sizes.

I think they keep the 4" in the line up so that it doesn't throw a monkey wrench in police acquisitions. Duty equipment is geared towards the 4" so If a large department purchased new guns and no 4"ers were available, it might be a big logistical problem. The 4 1/4 let them export for the Canadian markets. The new 19 and 66 are offered with 4 1/4. So is the new Python. A lot of Canadian security firms still use revolvers so I guess there is enough of a market to change the 4" revolvers to 4 1/4.

4.25” barrel and guide stick out about .25” from the front of a 4” slide…

Scoured the internet for. 4.25 barrel and guide rod, only to find out the that I purchased a FDE 4” optics ready slide from the gun show. Also learned upon receiving the parts that one of my guns is a 3.6” compact. Just happened to be the one I intended to put the new slide on…. :-)

It would seem to me that just puttin g a 4.25" barrel in the 4" slide would make more sense economically that machining a whole new slide length. But hey, I'm just a lawyer

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Forum consigliere

If you use the rail on the frame as a reference, it appears that the frame/lower is the same for every barrel length for a specific caliber, including the 4.6" and 5" if available.

I knew/know all that. Means we have compromise. And lose our 4" guns. Be easier if they just welded a nut on the front of the guns going to Canada.

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S&W Accumulator

Here's my take which I believe is accurate.

It took a LONG time for Smith to release a 4" answer to the Glock 19. I believe 4.25" was chosen because it was close to the G19, slightly more concealable than a G17, yet legal in Canada. The 4" came after about a decade of people asking for it (mostly for the grip). A little extra sight radius and a little more concealability is always welcome in my opinion. If I was an LEO, obviously I would go with a 4.25". Concealing appendix, I'd rather a 4" with a full-grip. If I was carrying IWB at 4:30, I'd rather a compact grip. If I was concealing OWB I would rather 3.6", etc.

I commend Smith because it gives us a lot of options, but the truth is that it was born from compromise. The original M&P9s were 3.5, 4.25 and 5" if memory serves me correctly. I had one of the first 3.5" compacts, but I've owned everything but a 5" at one time or another. The 4" enabled Smith to compete more directly with the Glock 19. If they had deviated too much from 4.25" in favor of a 4.5", for example, holster & parts compatibility would become more of an issue.

So then why is my Marlin 39A called a “Mountie” when it’s the shorter barrel version?

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Thirty characters. Exactly...

Don't forget about the 3.6" version. I picked up one of those recently. It's the same length as my 1.0 M&P9c. But it has the 2.0 compact grip frame, uses the 15rd mags.
I like the feel of it, it's a nice option, except North of the border.

Yup. That is why Ruger revolvers are 4.2" barrels, not 4"

"Could it be the metric system?" I mean the quarter pounder.

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"Don't Give Up the Ship"