highest power factor through a Shadow and/or 85 combat?

[cpa5oh]

I think there are alot of benefits to practicing with higher power factor gun/ammo and then competing at a lower (minor) power factor. Mainly, it makes grip and recoil control a priority in every practice drill I shoot. That helps me (I'm only a shooter of a little over a year.)

With Glocks I can shoot my G35 in major .40 for practice and then shoot a G34 in 9 minor in matches.

And frankly, I can shoot the Glocks flatter than I can the CZ's...yet the CZ triggers (with the SRT disconnectors) are unbelievably good.

Obviously there's no .40 Shadow...so the question - how hot could I safely load my 9mm practice rounds to shoot through my Shadow? I know there are guys that have turned 75's into open guns, so I would think I'd be okay at 9 major power factors...but figured I'd better ask and get some thoughts before I do it. (I'd use a different powder than I use 9 minor and I'd work it up slowly over time.)

[kneelingatlas]

I wouldn't go much higher than 150pf without a comp, I've shot 180pf out of my CZ Open gun but a compensator counters some of the force on the barrel linkages.

[burningsquirrels]

I usuallu fly through the chrono at 142....

[motosapiens]

PF is not really that relevant. It is chamber pressure that you should be concerned about. If you use a max load of power-pistol or some other slow-burning powder, I'm pretty sure you will get significantly more recoil than with a 130pf race load.

Even at the same pf, power pistol produces a much bigger kick in my 40.

[kneelingatlas]

Good point Moto

[cpa5oh]

I'm not looking for simply the difference between two different brands of powder making the same power factor - honestly, when people talk about one powder shooting softer than the other for 9 minor, I might notice a tiny difference but not enough for it to matter. I played a trick on a guy at our club who had two different loads where he swore one shot softer than the other - I mixed his bullets into a magazine and wrote down the order and had him tell me which shots were with his "softer" load and he was worse than 50% in identifying his hot setup.

I'm hoping for the difference between minor and major power factor, if possible. Is that not possible? Open guys are running 7-ish grains of AutoComp, for example...what if I took that powder and stopped somewhere short of 7 grains?

[kneelingatlas]

6 grains of HS6 should give you what you want. I would use a plastic guide rod or a recoil buffer to avoid tearing up you pistol.

[cpa5oh]

Will do both - thanks so much!

Dan

[JamesLovesJammie]

You don't need to have a Shadow upper. Any CZ .40 upper would work. Just remove the firing pin block and spring from the slide. Voila. Shadow upper.