It seems to be a bit of play in both the barrel to the adapter and the adapter to the receiver. PLA+ adapter is providing the tighter fit with the PLA+ upper. I decided to wrap a couple layers of teflon tape around the barrel, but fewer layers around the pin holes in the barrel. It Is now a much tighter fit in the adapter. I actually added additional layers another two or three times after test fitting each attempt.
I then wrapped the barrel adapter with a couple layers of teflon tape as well and it is much better than before. Instead of just under 1/2” horizontal sway of the barrel, it is now down to probably 1/8” or even less. It seems to be a tolerance issue…and that may be a result of the RS22 barrel itself since it was a $35 barrel shipped from Rossi. I further bubba’d it with a black ziptie around the barrel from each side of the end of the handguard and now it is really rocksteady. The two zip ties are pulling equally from both the right and left sides of the handguard. I know my experience is not what is intended, but it seems cable ties and pipe/duct clamps are a natural fit for 3D2A anyway.
As for settings, I printed all the Polymaker PLA+ with 300BLK’ settings. Now I just need to get to a range to finally test it with live ammo, as dummy rounds are functioning quite well. Again, this has been an educational and fun project that reminds me of working out the kinks in the first P80 I built.
I have an A1 Mini and the Top Cube zippered enclosure. I leave the front open when printing, but the case is mainly to prevent my kitten from biting the tubes…she thinks she’s a puppy. I did complete the Noctua 4020 motherboard fan upgrade as well. Temps inside never get to the max recommended temp of 30C from Bambu. I also have a Bento Box installed in the back of the enclosure. Now that you know my specific arrangement, I’ve been able to print Fiberon PA612-CF without issue using 300BLKFDE’s settings. PA612 is a blend between PA6 and PA12, so it should last much better on a can than PLA+…but maybe not as well as PA6CF. I do have a roll of Fiberon PA6CF coming with my monthly subscribe & save from Amazon from the end of the month.
Some people like to print PA6-CF above 300C, which my A1 Mini can’t do without modding…which I don’t want to do.