Grand Power 3rd trip

[Intercooler]

  Last night I tried a different oil/grease setup for today's visit. I used CLP on the barrel breech face/slide rails and Magnalube (had the stuff for a long time) on the rotating barrel and locking lugs.

[Intercooler]

  I chose all factory best ammo for the first 200 round and it buzzed them off perfectly!



  At that point I switched to Perfecta and had a stoppage at round 28 which was a weird poof.



  I had another poof at round 32 and then switched to the EAA Limited. It also had two poofs finishing the box out. This ammo has some issues!

[Intercooler]

Shortly after the 28th round failure shooting the Perfecta ammo I had another one at round 32. I then switched over to the EAA LImited (which never fails) and had two more poofs. I didn't get the stoppage in the Limited, but the sound was the same and I attribute it still running to the weaker recoil spring and non-rotating barrel. If the Grand Power had one of the weaker recoil springs I have on order in it, I'm pretty confident it would have just kept on chugging through the remainder as well.
The Grand Power is accurate like the EAA's and feels really similar in the hand. Given what I did with the grease last night and CLP, that will be how I run it going forward. I think oil just doesn't stay on the rotating barrel like it needs for perfect operation, due to cycling so many times quickly (spin-off). It's a little more sensitive to ammo due to the tight machining IMO and will tell you what it likes or doesn't like. I have never been much of a fan of plastic guns, but I'm looking to keep this one due to how much fun it is to shoot. It looks like lube, ammo and springs will get one of these 100% if you can endure sorting it out.
Now I have to sit down and figure out what's up with that Perfecta ammo! I have three cases of it and plan on weighing some tonight to see if I can find some light ones. If I find something I will send them down to Wade for pull-downs to see what's up.
My only suggestion to the Grand Power group is more springs in set weights (love the colored ID, just need ratings for each) for these pistols. The Grand Powers don't seem to be on the radar from what Wolff said the other day when I ordered springs. They hinted about needing some platforms to get a spring set for them. Is that possible? I see the 10mm version needing a 18-24lb springs to run the range of ammos in them.

[DM1906]

Good report! It's great to hear the pistol is running. I don't know about that ammo. 9mm is the only caliber I've seen local and haven't shot. I have a few thousand rounds of .40 and .45 downrange without so much as a hiccup in a dozen pistols. None of them new, or as new as yours. It appears clean and the brass looks good, though.

[Intercooler]

  When I got the poof sound like an undercharged round in the Limited I knew it was the ammo. I should have consolidated the brass from those to see if it showed anything and failed to do that. It's either a low charge or something with the primers in those.

It's a funny smelling powder, but seems clean. Here is what The Shadow found:

PERFECTA      115   FIOCCHI   FMJ   1,150   1,094   1,148   305   337   RAMSHOT SILHOUTTE    5.2   

http://10mm-firearms.com/factory-ammo-pull-downs/underwood-9mm-115gr-speer-gold-dot-jhp/msg34268/#msg34268