Rock Island GI .45 1911 suitable for .45 Super conversion?

[Deaf Smith]

Been thinking of getting a Rock Island GI .45 1911, 5 inch bbl. and turning it into a .45 Super (I understand one just puts in a heavier recoil and firing pin spring.)

Do you think it would take the pounding?

Thanks,

Deaf

 

[P71pilot]

Really that is not all that SHOULD be done when converting to super. A heavier mainspring should be added, as this will help keep the gun locked up longer, which will allow pressures to calm down before violently starting the cycle of the machine. A flat bottomed firing pin stop is generally recommended as well.

As for the host itself, i would say a PROPERLY FITTED RIA should do just fine, just understand that the parts are not the highest quality so you will definetely prematurely wear out parts, especially if you shoot a ton of ammo through it. Luckily 1911 parts are easy to come by and fairly inexpensive, learn to look out for worn out barrel links and barrel lugs, takedown pin fit

 

[RickB]

You will need a heavier recoil spring, but I'd rate that number three in order of importance in converting a .45 ACP to .45 Super.
1) 25# mainspring
2) Reduced-radius or no-radius firing pin stop (EGW or Harrison Design)
3) 20#-24# recoil spring, as necessary

Even max loads are running lower pressures than 9mm, .40, or 10mm, so as long as the gun doesn't have some glaring problem with barrel fit, you should be OK.

 

[Aguila Blanca]

Armscor (Rock Island) sells 1911s chambered in 10mm, so they must think their parts will take the punishment.

 

[g.willikers]

How are their frames made?
Machined forgings, castings?
Might make a difference, especially with reloading and possible errors.
Also might depend on how much you intend to use it.
A similar model in 10mm might suggest the .45 is strong enough.
Might not.
Kind of like high performance engines in production cars that are meant for stop light grand prixs and other momentary thrills.
For actual racing, they might be less likely to hold up very long.
Some do, most don't.
Just a thought.

 

[T. O'Heir]

You looked into the cost and availability of ammo/brass? Ammo apparently only comes from Buffalo Bore. Midway wants $50.99 per 50. Double Tap supposedly loads it too. Not available through either Midway or Graf's though.
Brass only from Starline. Unreliable delivery via Midway. Graf's wants $27.99 per 100.
Seems lots of people have the same idea. 29,500 result from a Yahoo net search for '.45 Super Rock Island pistol conversions.'. Mostly a lot of useless arguing though. Armscor says, "Each firearm is built using 4140 Ordnance steel..." CNC machined.
Anyway, this was discussed here in 2012.
https://thefiringline.com/forums/showthread.php?t=493977

 

[Aguila Blanca]

Armscor's frames are investment castings. Yeah, I know ... "cast" = bad. Whaddaya think Ruger Blackhawks are?

Armscor's slides are extrusions. Extruding is a form of forging.

 

[Mike_Fontenot]

Ammo apparently only comes from Buffalo Bore.

Underwood sells several options of .45 Super on their webpage ... that's what I use in my SW1911-Pro .45 Super.

 

[chuckscap]

Don't know if it's in your budget but the Springfield V16 was built for 45 Super. They're around but hard to find. I shoot regular 45 ACP hardball, 45 Super handloads (I have lots of Starline 45 Super brass) and Buffalo Bore 255 hardcast at 1075 fps. I'd call Rock Island and see what they think or Ace Guns if they're still around. They used to own the patent/copyright on 45 Super.

 

[Mike_Fontenot]

Been thinking of getting a Rock Island GI .45 1911, 5 inch bbl. and turning it into a .45 Super.

Have you considered a Rock Island 10mm? I think 10mm is a better round than .45 Super. (I have both. I got the .45 Super (SW1911-Pro) because I thought it might be more reliable than my 10mm Kimber Eclipse Custom II. The jury is still out on that.)

 

[xcc_rider]

On the subject of 45 super reloading brass, I've read they started out using 451 Detonics Magnum brass cut down to 45 ACP case length.
IIRC, you could also cut down 308 brass for the 451 mag. If so then couldn't you make a crap load of 45 super reloading brass from all the discarded 308 range brass?

Of course Starline makes 45 super brass now but if the above is correct it would really cut down on the reloading costs.

This is probably a question for the reloading forum but since reloading brass was mentioned I figured it flowed with the main topic.

 

[g.willikers]

I tried using cut down .308 brass for .45acp reloading.
Way too thick for my Dillon Square Deal progressive to size.
Got a good workout trying, though.
It might work with a heavy duty rifle caliber press.

 

[RickB]

I did some measuring of case internal volume, and could see no clear correlation between implied case strength and case capacity.
That is, you'd think .45 Super would be stronger than .45 +P, and that +P is stronger than .45 ACP, but internal capacity varied more by brand among .45 ACP cases than in a clear order of lower internal volume = greater strength.

.451 Detonics was obviously thicker around the case head, with a very narrow extractor groove that closely resembled .30-'06/.308 construction. The factory .451 conversion kit included a case neck reamer so that trimmed .30-'06/.308 cases could be internally relieved for bullet seating.
I have more than a few G.I. .45 ACP cases that also look like they must have had the case heads formed on the same equipment as .30-'06/.308 cases, with a very narrow extractor groove, but I don't know how much the extra material alone increases case strength?