[schmeky]

The other night I installed a heavier recoil spring in one of my semi-auto pistols. Before I made the swap, I decided to push down on the barrel hood (CZ pistol). After I installed the heavier spring, I did this again. It seems as though the barrel is more positively locked in battery now.

My question is: can recoil springs potentially influence accuracy?

[rcmodel]

I doubt it.
I base this only on my experience with 1911 NRA Bullseye guns. How it relates to CZ's I cannot say.

But as long as the weaker spring returns the slide to battery and lock-up is consistent every shot, holding it in the same position, only tighter, should have no effect on accuracy.

Our Army AMU center-fire guns used very light springs for use with SWC mid-range loads.

They were capable of shooting higher scores then the hardball guns that had full power recoil springs. That is probably mostly attributable to the pound lighter lighter trigger pull allowed on the center-fire guns.

If a heavier spring would have made them more accurate, I would have had to see it proven in a Ransom rest, and I didn't.
They would already shoot one-ragged-hole 10 shot groups at 50 yards.

rc

[schmeky]

Thanks RC. I ask this because the CZ pattern pistols use an oval shaped cam under-lug to position the barrel in battery. It would "appear" a stronger spring would tend to more positively cam the upper lugs into their corresponding slide lugs.

I know the CZ Custom Shop sends out all their Custom SP-01 9mm's with 11# recoil springs (stock is 14#'s).

I may do an inpromptu range test one day. Probably makes no difference.

[Oro]

I ask this because the CZ pattern pistols use an oval shaped cam under-lug to position the barrel in battery.

That was going to be my guess before I read your response. I'm not experienced with CZ's, but I do know some Autos use a camming underlug pivot to translate horizontal recoil spring tension into vertical engagement force. There is an equivalent device you can purchase for a 1911 called a "Dwyer Group Gripper" - now sold by Wilson Combat.

Your new spring may be giving more vertical tension, but I doubt it will make a noticeable difference. What matters is consistency, and as long as your old, weaker spring was giving consistent lock-up, then it's going to be a wash in terms of functional accuracy.

[CZguy]

Your new spring may be giving more vertical tension, but I doubt it will make a noticeable difference. What matters is consistency, and as long as your old, weaker spring was giving consistent lock-up, then it's going to be a wash in terms of functional accuracy.

It's been my experience that it doesn't make any difference as far as accuracy.

I've never run any specific tests for this, but I have played around with different springs on CZs quite a bit.

[1SOW]

scmeky: I know the CZ Custom Shop sends out all their Custom SP-01 9mm's with 11# recoil springs (stock is 14#'s).

Like rc, CZ is tuning them for lighter loads for competition.

I'm shooting 11# in my 75B and can't claim any change in accuracy other than the lighter recoil benefits MY accuracy by deemphasizing my shooting faults.

Does testing the lockup with the gun stripped and no spring in place (using gravity)indicate anything significant? It does feel tight front to rear..