Soft Loads - 9mm PCC versus 9mm 1911

[RickT]

Currently using 115gr Bayou with Sport Pistol in both platforms for Steel Challenge.  I'm new to PCC, but wife and I have put >150K rounds through our handguns.  3.4gr SP is about as soft as will cycle the 1911, but both my 16" (full rifling) and Wiland barreled PCCs will cycle with 2.8gr SP.  I've been using in the 1911 a 9 lb. recoil spring and 19 lb. main spring forever.  I don't need the 1911 to run softer, but I'm an old guy who likes to tinker.  Is there a message in this data that I should try backing off on the 1911 springs or is there something about the PCC recoil/ejection dynamics that just lets them run with that little charge?  I'll probably just take my backup 1911 and change the springing, but I'd be interested on anything someone might have to offer on this phenomenon.

[jcc7x7]

As long as the recoil spring strips the round out of a full mag and locks the slide up you're good to go!

I've run some with 7 lbs springs but it needs to be run clean and well lubed. then it will run a 200 rounds before it gets sluggish.

So like you I usually run 9 lb springs because the gun runs and split times are the same as far as sight recovery etc.

Give a 7 a try and see what happens, I don't like going below 19lb MS, but that's me !

[zzt]

My custom 1911 Open gun has a 7 lb. conventional recoil spring, 19 lb. mainspring, and a firing pin stop with a high radius.  The slide has been lightened to 10.5 oz.  It runs fine with 140PF Open loads.

 

I fitted a Barsto bull barrel to it so I could shoot mouse fart loads, hoping to be able to use the same load in both the PCC and the 1911.  So far, both will reliably cycle 109PF loads.  I tested some lighter loads in the pistol yesterday, but did not chrono them.  The 125gr load shot fine.  The 105gr load just dribbled out.  I'll try them in the PCC this week.

 

I'm also new to PCC and have been experimenting.  A lot of what I found runs against some of the conventional wisdom.  For example, In my light rifle, 5 lb. 7 oz. with C-More Railway installed, the dot bounces with light loads.  Same thing with factory 115s and 124s.  On a lark I shot a bunch of factory 147 JHPs @ 990 fps.  Recoil was harder, but straight back and the dot did not move.  The second rapid shot hit exactly on top of the first at 50 yards.  I ran through a box of ammo confirming this.  Frankly, I was surprised.

[MemphisMechanic]

@zzt that’s only against conventional handgun wisdom.  

 

Short stroked guns with a well tuned buffer & spring at 135-145 powerfactor are pretty unviersally accepted as the flattest-shooting AR-9 setup in the PCC forum.

 

Gotta get the new guy with a rifle to stop thinking softness, like he wants his handguns to run, and start thinking dot movement & flatness. 
 

Edited March 16, 2020 by MemphisMechanic

[RickT]

Good information.  I shoot SS so neither bull barrel nor light slide for me, but I might give the 7 lb. spring a try.  Interestingly enough while testing some even lighter PCC loads yesterday (2.7gr SP with the 115gr Bayou bullets I found that the 1911 would actually cycle a 3.1gr load (versus my usual 3.4gr), but just barely.  The temperatures are getting warmer in Idaho so I think that's part of what's going on. 

 

The Wiland barrel rifle is just at 5 lbs. and my wife needs the softest load I can make.  When I get the tax stamp for my 8" CMMG upper I'll experiment with loads.  I have plenty of WSF which would be a good powder for 145gr bullets and would likely create more of a push.  Being also new to PCC I've got to experiment on recoil management, not that there is much, but a heavier bullet should help keep the reticle on target.

[RickT]

1 minute ago, MemphisMechanic said:

@zzt that’s only against conventional handgun wisdom.  

 

Short stroked guns with a well tuned buffer & spring at 135-145 powerfactor are pretty unviersally accepted as the flattest-shooting AR-9 setup in the PCC forum.

 

Gotta get the new guy with a rifle to stop thinking softness, like he wants his handguns to run, and start thinking dot movement & flatness. 
 

Got in before your post.  Yep, wife needs very, very soft.  I do want flat shooting.  My heavy 16" barreled gun is flat with these soft loads but I may have to tinker with the shorter, lighter version.

[MemphisMechanic]

@RickT short verison on PCC recoil managmeent?

 

Mount the heel of the stock on your pec kinda under the dominant eye, torso fairly close to square to the target. It’ll drive chest straight back instead of rotate you, like it does out at the shoulder. (The dot will track more vertically, not diagonally like it does if your shoulder rocks back with the stock out there.)

 

Grip the handguard way out there with the weak hand and drive it HARD back into your chest. Engage your core and drive your chest forward, into the gun. You should not need your firing grip to support the rifle. Clamped into place at both ends, it’ll move much less when fired.

 

Lean into the gun and get your weight on the ball of the front foot.

 

Observe dramatic reduction in dot movement.

 

Edited March 16, 2020 by MemphisMechanic

[zzt]

5 hours ago, MemphisMechanic said:

Short stroked guns with a well tuned buffer & spring at 135-145 powerfactor are pretty unviersally accepted as the flattest-shooting AR-9 setup in the PCC forum.

 

I shot loads in that PF range on Sat.  Then I short stroked the gun and recoil increased.

 

4 hours ago, MemphisMechanic said:

Grip the handguard way out there with the weak hand and drive it HARD back into your chest. Engage your core and drive your chest forward, into the gun. You should not need your firing grip to support the rifle. Clamped into place at both ends, it’ll move much less when fired.

 

That is exactly what I did with the 145 PF load and the dot barely moved.  I t was back on target before I could get subsequent shots off.  I was firing as fast as I could pull the trigger.  I'll load up some 124s at 1100 and 1150 and see what happens.

[MemphisMechanic]

Short stroking does often increase felt recoil, but that doesn’t mean you should abandon it.

 

As stated above, we’re taking softness entirely out of the equation. That’s not the goal. Adding felt recoil is just fine if the dot flattens out, right?

Whether it gets flatter with a given modification will come down to your buffer, spring, the bolt’s weight, you comp, your bullet’s weight & velocity. And a host of other factors.

It’s puzzling reading posts where experienced large men are firing a 6 pound handgun from their shoulder, and they’re focused on making the gun shoot more softly.

 

Setting it up to chew one ragged hole as fast as you can work the trigger is what matters.

 

(Note: I’m referring to PCC setup for an experienced competitor. If you’re building the gun for your recoil-shy wife to shoot, as mentioned above? That’s a whole different topic.)

 

Edited March 16, 2020 by MemphisMechanic

[RickT]

Good points all.  Setting aside the value, or lack thereof, of soft shooting rounds it isn't obvious why the energy that will cycle a 3-stage Taccom bolt in a 5.5" barrel PCC won't cycle a softly sprung 1911.  Heck, the soft rounds will lock the PCC bolt back despite the heft 3rd stage spring of the Taccom bolt.

[zzt]

There is nothing holding the bolt closed in a PCC other than spring pressure.  A 1911 barrel has to be unlocked before the slide can move all the way back.  Load one round in a mag ans shoot it.  The very worst that can happen is the bullet gets stuck in the bore.  I don't think your loads are anywhere near that light.  So extraction will be your issue.  I've shot loads so light the barrel unlocked but the slide barely moved back and rechambered the spent case.

[RezRocket]

For 3 gun I like the 147 blue bullet PF of 133. Tied Missouri Bullet company too just as good in my opinion. I like to keep the PF up a little for the poppers and KO steel.