1911 caliber swap.


February 13, 2013, 09:01 PM
Hey y'all,

I recently bought a RIA 10mm Tactical II, and am thrilled with it thus far - the thing is well set up and shoots beautifully.

Here's my question:

Since the 1911 is a standard platform, how easy/hard is it to change calibers in these things? The RIA comes fitted with a bull barrel, which either makes things more or less difficult.

(As you can see, I have no idea what I'm talking about on this one.)

Put bluntly, 10mm is damnably expensive, and I don't reload - can I use this as a platform to, say, put in a new barrel/bushing/bull and run 9mm?

That would be cool.

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February 13, 2013, 09:44 PM
Nothing is really drop in with a 1911.

I just spent several hours fitting sights that you would think could drop in.

As for your caliber change, you are stuck with whatever uses the same style feed ramp and is close enough to fit the same in the bolt face. You could probably get a barrel chambered in .40 S&W and maybe make it work with .40 mags if you can find those. You would have to have the barrel fitted.

Probably cheaper to just buy a reloading setup and make your own 10mm rounds.

If you had a 38 super you could do 9mm and 38 special wadcutters.


February 13, 2013, 09:45 PM
A .40S&W barrel would likely be a safer bet, but 1911 barrels are not drop in and there are three styles -- un-ramped, Wilson, & Nowlin. Bull barrel makes it more difficult, as Storm-Lake 1911 barrels (and many others) come with a pre-fit bushing -- you may only need a little fitting on the outside of the bushing so it fits your slide.

Call RIA, if the ejector is comparable they may sell you a complete 9mm upper at a reasonable price. As far as I know none of their 9mm models use a bull barrel.

February 13, 2013, 09:53 PM
Getting the whole upper is a good idea, and probably cheap from RIA.

Didn't think of that. In the same vein you could get a .22 conversion upper.


February 13, 2013, 09:56 PM
A 9mm barrel & bushing might very well work with a 10mm breechface and extractor, but you are going to need a 14-16lb spring and 9mm magazine to make it work reliably. The 10mm might be issued with a 20-22 lb spring, and it just won;'t let a 9mm blow it open. The 9mm mag positions the 9mm round properly, and will feed more reliably. A 10mm might be more easily be converted to .38 super, as the rim sizes are closer, but that isn't going to help you with ammo costs.

February 14, 2013, 12:13 AM
10mm, welcome to the world of handloading if you want to shoot it enough to be proficient with it. :)

February 14, 2013, 10:38 AM
Thanks for all the advice folks.

I know I have to get into reloading - it's on the list.

A 9mm "upper" would be cool though!

February 14, 2013, 12:42 PM
Put bluntly, 10mm is damnably expensive, and I don't reload

You didnt know this before hand?

The up side is you can probably pick up a complete used Rock Island 9mm/45acp cheaper than toying with your 10mm..

February 14, 2013, 01:17 PM
Springfield built a long slide 1911 style called the Omega that came in a case with a 10mm barrel and recoil spring, .45ACP barrel and recoild spring, and a .38 Super barrel and recoil spring. FOr whatever reason they never sold or never went into full production. The one I shot as a gun rag writer back in the 80's was great.

My understanding was that the 9mm required a different ejector which is mounted in the frame and not a normally removed by the user item.

When the US Army was looking at converting the WWII stock of 1911A1s to 9x19mm NATO this was also an issue. They were looking at replacing the slide assembly (complete with barrel et al) and depot modifing/replacing the ejector. They decided it was not cost effective compared to simple replacement.

Another item Springfield made and sold more of but which seem rare as hen's teeth now was their SASS Springfield Armory Single Shot which was an "upper" that replaced the slide group to convert the 1911 to a single shot pistol for calibers up to .308 Winchester/ 7.62 NATO. Not sure what happened to those either as far as wear adn tear on frame groups. At the time I was occassionally shooting a friend's old Merrill in .30-30 and I wanted a SASS of my own.....but was a poverty stricken student at the time.


February 14, 2013, 02:28 PM
I had this same question when I bought my 9mm 1911, thinking I could just throw a .45 top end on. All research and answers said that the feed ramps are cut at different angles, so it won't work. I'm assuming it would be the same problem going the opposite direction, .45 (or 10mm) to 9mm.

February 14, 2013, 02:36 PM
I have a full size S&W1911 .45 ACP

I also have a Bar Sto barrel in .400 Cor Bon

For 9mm I have a CZ 75B $500 or so


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