I have been contemplating getting a Cav arms lower to start making into a pistol caliber rifle. From what I have gathered, they seem to be the best way to go if I want to do one in .45.  That's fine with me, because they also seen to be the most cost effective. I will admit I'm lost when it comes to uppers though, can someone steer me in the right direction? I would like to piece it together as I accquire funds, but I have a feeling I might be better off saving and buying a complete assembled upper. Any words of advice?? TIA, Bill

Olympic Arms 45 cal complete uppers run from $400-600 for used-new.  You can find them on the EE or from one of their distributors like Atlantic Firearms. www.atlanticfirearms.com/

You can get the grease gun mag adapter from brownells. www.brownells.com


Grease gun mags
www.northridgeinc.com/machine_gun_parts.htm

www.e-gunparts.com/product.asp?chrProductSKU=198850B

www.keystonearms.com/mags~non.html

Great info, thank you.
I was wondering also, do you use the .223 recoil spring/buffer assmembly or is there a .45 specific one?

Quoted: Great info, thank you. I was wondering also, do you use the .223 recoil spring/buffer assmembly or is there a .45 specific one?

You can use the spring but you need to use a heavy buffer. Thats all I got

THE .45 ACP thread
45 ACP, CavArms-Hahn Block-Grease Gun Mags-Oly Upper

Explains the need for buffers, links to Slash's custom buffers, drawings to make your own, plus a lot of Lessons Learned by other builders.

Here is my thread on my set up....

My Review....

Thanks guys!

Unka........

I'm building one.......do you want me to make a thread on it?

That might not be such a bad idea.............I might get jealous though......
Thanks!

Yes a thread would be nice. I would like to make one too.
I guess I need a CAV MKII lower, a .45 upper, mag well converter and a heavy buffer. I guess you can use a .45 barrel on a any receiver. What about the bolt?

does the bolt have to be modified??? For 9mm dont you have to ramp your bolt??? Is it the same for .45???

Please forgive my noobness and I might be totally off here

Quoted: does the bolt have to be modified??? For 9mm dont you have to ramp your bolt??? Is it the same for .45??? Please forgive my noobness and I might be totally off here

I think we are getting pistol cal upper "styles" mixed up here.  The two "main" styles are:
1) Colt- there is only 9mm from the factory and clones.  Mag well adapter is either 2 piece or single drop in from top or bottom.  This style usually gets the carrier machined so it cocks the hammer better. Ejector is on the mag well adapter....usually requires a 9mm hammer or modified 223 hammer to work.  Colt style is what RRA "copies".  (There has been a custom 357 Sig in Colt style, along w/ some other cals.)

2) Olympic- pistol cal. in 9, 40, 45, 10mm.  Uses a cone shaped chamber/ramp.  Ejector is a "spring" mounted on the upper unit. System works on any lower w/out any modification (note-ALUMINUM lower, the Cav plastic is exception....don't know about Vulcan Carbon Armide lower...)  Oly made/modified mags usually have a spacer welded on so no mag block is required....but mags end up expenisve.  SOCOM block used for Sten mags to feed 9mm (and 40) while 45 uses Uzi 45 mags w/ spacer welded on.

3)Weird hybrids.... they are out there..... not worth mentioning since they don't hold a "significant" part of the market.

Any how, there is no need to appologize....most people don't know there are differences between the Colt style and Oly.  Note the "blue"....that's the main stuff....