I haven't shot a semi auto 22rf for a long time now. I don't even have one tucked into the back of a safe. The last one I used was a Pietta, ppsh clone with a 50 round drum.
It was a good rifle, but nothing to get excited about. After a couple of mags, accuracy quickly fell off and it needed to be cleaned. It was used to cull a lot of Richardson's Ground Squirrels.
It shot much better when cleaned every 50 to 100 rounds.
I got into the habit of cleaning all of my 22rf rifles after that much shooting, when keeping count. If not, while at the range and notice the groups opening up.
All of my subsequent rifles are definitely more consistent shooters from a cleaned bore.
I find that they seem to like any cleaning residues or bore lube wiped out to a dry bore to shoot well on the first shot, after cleaning.
The one thing I find about 22rf semi autos is that if they are shot with some time to cool between the strings allowed with full magazines, foul very little. On some of them, there can be a noticeable difference in accuracy after a couple of mag dumps, especially the 25 rounders. I was out shooting with my grandson, last spring. His Dad gave him an AR lookalike, along with three 20 round mags. We went to the local club range for some plinking fun. Four inch balloons at 25 yards, offhand.
He's sixteen. His idea of plinking fun is to see how quickly he can dump the mags, in a spray and pray fashion and maybe actually hit one or two of the balloons.
After a couple of hundred rounds of this, I noticed a bit of shimmer coming off his barrel. It was HOT. To hot to touch comfortably. Yes he was loading it with Stingers, but I didn't think it would get that hot.
We hadn't been checking it for accuracy, so didn't notice any degradation. When he finished his sixth string of all three mags, 360 rounds, I asked him to stop shooting and feel the heat from his barrel. He just laughed and said it was normal, which is quite likely from that sort of shooting, which I have nothing against.
I asked him to let me have a look at the rifle, so I could check out the bore. Surprisingly it looked quite clean, other than what appeared to be powder residue.
I asked him if I could clean it and he was ok with it, after commenting that he and his Dad had put at least 10k rounds through it over the last couple of years.
When I cleaned it, it really wasn't bad.
For tough cleaning chores, that need to be completed quickly, I use a mix of 50/50 vinegar/hydrogen peroxide (the weak stuff for human use, about 3% peroxide)
This stuff will get rid of old, packed down lead based bullet material, left behind in bores pdq. It needs to be used properly though and with care.
There wasn't a lot of lead residue in that bore, but there were a couple of noticeable bits on the bottom of the plastic bucket (this stuff is nasty, dispose of it properly and use it outdoors)
I poured the used solution, through a cloth filter, into another bucket, so I could look at the bits. They were definitely bullet residue and may have been packed in tight against the rifling.
After this procedure, the bore was flushed with lots of water and given a coat of mast grease (incredible stuff that works, but needs to be cleaned out before shooting continues)
After a quick wipeout, the bore looked like it was new, with the naked eye and a small light.
I shot the rifle, off the bench, to see how well it would shoot.
The first shot was a flyer and my grandson was visibly unimpressed and maybe worried that I had buggered something up. After three shots, it all came together and that little clone, put the rest of the magazine into a neat little group, just over an inch in diameter, without any difficulty. Not to bad for 70 year old eyes and iron sights.
This is a bit off topic but still similar. Mc CZ452, chambered in 22rfmag definitely likes to be cleaned at least every 50 rounds or so and likes at least one fouling shot.
