Kimber .22 Conversion Kit Questions

[NeverAgain26]

I played with a Kimber Conversion Kit at the range and decided to buy one to sit atop my Kimber CE II 45 frame. The friend who let me play with it told me that he had his smith put in a lighter Hammer Spring in his frame in order for it to cycle .22s and 45s with the same spring. I was wondering whether I might have to do the same thing with mine.

I did a search on THR and came away confused. Standing Wolf in several posts posted that he changed his main spring. Several members opined that the recoil spring might be what everyone was talking about, but Standing Wolf seems to know the difference between a recoil spring and a main spring and he was certain that it was the main spring that was adjusted. This fits with what my friend told me.

My questions (to anyone who has a similar set up and/or to anyone who is knowledgeable on the subject) are as follows:
- What does the main spring have to do with the gun cycling reliably in a lower caliber? Would a heavier spring affect the cycling of the gun? I thought the recoil spring would play more of a part in that function. The kit has it's own recoil spring which seems to be perfect for a .22 recoil.
- Doesn't the main spring just trigger the hammer to fall and drive the firing pin forward? What difference what weight it is (unless it were too light to strike a primer for a larger caliber)?
- MUST I change the main spring on the frame of my gun or can I avoid that by shooting High Velocity Ammo?
- As I have a big box of Federal Match Ammo, could I use that without changing the springs? My friend told me that the match Ammo is not High Velocity.

Additional information:
- I shot it on both my frame and his frame the other day and had no problems cycling the slide using his Remington Ammo.
- Today, on both his frame (with the adjusted spring) and my frame (with a stock .45 main spring using the Kit) I had problems cycling the slide after firing (this using both my Federal High Velocity Ammo and his Remington).

I already bought it and it should be on the way. I am not about to change it for a Marvel or a Ceiner and I want to make what I bought work.

Anything anyone can do to clear up the subject for me would be most welcome. Thanks in advance for your help.

Saul Levy

 

[JoeHatley]

When the slide moves back, it compresses the recoil spring. The hammer is also cocked at the same time. As the hammer is cocked, the mainspring is also compressed. Everything works together.

Target ammo may not be powerfull enough to compress both springs. That's why most conversion makers recomend high velocity ammo.

Swapping out the mainspring with a lighter one, may allow target ammo to cycle, but there is no free lunch. A lighter mainspring may cause misfires.

My Ciener kit requires a full power mainspring to fuction reliably.

This amimated view may help: http://m1911.org/full_1911desc.htm http://m1911.org/images/full_anim.gif

Good Luck...

Joe

 

[NeverAgain26]

Joe, U D Man. That was very understandable (without even viewing the animation). Thanks.

Now if I can hear from someone who has/uses one of these on a Kimber and what their experience with the kit is as far as springs, I would have a better idea of which way to go.

I guess I have to get it, play with it and see what happens with different brands of High Velocity ammo, in any case.

Saul Levy

 

[mljdeckard]

I use stingers and velocitors with my Ciener/Kimber combo. Other ammo works fine for about 200 rounds, then I have to clean. I never even considered switching out a mainspring to make it better. That is taking a convenient idea, and turning it into getting a whole new pistol.