New SPA Artemis PP750

Between the 8" barrel, small plenum and 3mm ports it tough to break 12 FPE.

I opened all the ports, epoxied the channel around the barrel transfer port, aligned barrel transfer port, bored out plenum and extra 1.5mm, channels in the hammer, peek poppet, polished reg... only got me to 775 fps 13.6 FPE with the 10.34 and 825fps with JSB 8.4 in a decent 26 shot string. Dropped the scope to 1.3" above bore, reduced velocity to 750 with the JSB 8.4 for 30 shots within 1.6%. It's making 1/4" groups at 25 yds and super quiet. Already blooded in with a rat and a hosp, I will be operating in this range for a while, PP750 is great at 10-35 yards.

Hello all, 

Thane please can you post a picture of your hammer?

thank you 

Thierry

Sure, 3 channels so there is alway one open. Most of the channel is open top and bottom, last bit traps some air possibly slowing hammer. Channels are to release any trapped air and in theory increase hammer strike without additional spring tension.

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Looks like a good way to go. 

On another note - has anyone had issues with the looseness of the two trigger screw set screws? After shooting for a while one day I noticed the trigger started getting really heavy and not feeling quite right. Pulled the grip cover to see both set screws had started backing out. The front screw was actually 1/2 way to falling out. I tried some teflon/PTFE plumbers tape but it just wouldn't thread in well. I just added some 1500# helical grease to the screws (if you're not aware what this is, it is a sticky grease used on things like camera zoom lenses) - we'll see how that holds. I've thought about blue thread lock, but that puts things into a permanent position and may not set on a loosely threaded set screw. Any other thoughts?