Breaking in a PCP?

Firstly these are just personal observations. I only own four PCPs and started shooting PCPs two years ago. The one thing that I’ve done from my first PCP (Gamo Urban) to my fourth (Bantam Sniper HR) is run a few patches. Then it’s shooting time. A few tins of pellets down range and then I might think of “adjusting” or “tinkering”. 



I believe that the more diligent manufacturers tune/set their PCPs as close to their stated specs as possible. Then as received the gun should be allowed to settle in. With a new gun you as the shooter, by shooting it a lot are allowing parts to wear in together. Too many times a user will get a new gun, it’s shooting fine, might post some numbers (FPS, FPE, etc). Someone might chime in, about adjusting “this,” tweaking “that” to get “more” performance. Person starts to tweak away and then when things don’t get better. Or even get worse, blame the manufacturer of the product. Of course this doesn’t apply to those who know what they are doing.



For myself while I do think I have a simple understanding of how a regulator works, what a plenum does in theory. In practice I’m reluctant to make changes unless I have to. For instance I’ve owned my deadly accurate Compatto for over a year. No adjustments at all “out the box” to this day. I will be lightening the trigger, because the trigger on my Bantam is much lighter. The only thing I’ve done to the Compatto is change out the o-ring on the inlet valve. I will do the same with my Sniper, send thousands of pellets down range before I even think of tinkering with something that’s already performing to its specs. I want to get know my gun “before” I try and change things. The above has held true with my Urban (took tension off barrel band screw). pp700sa, same thing, break it in, start killing rats, no fussing, just shooting...



One last thing, 25 yards groups don’t mean a thing most decent PCPs can really group great at 25 yards. 50 yards should be the accuracy distance especially for the more expensive PCPs. 
 
As an engineer, I love to tinker with things. However, Ive also got my bone stock reliable guns. When you have unlimited access to cnc’s and software its hard not to mess with things! Its funny about your 25 yard comment, in the early 90’s I wouldnt of dreamed of shooting an airgun at 100 yards now its almost standard! Ive got an original kodiak and crowmagnum that I still love to shoot at 10-20 yards.
 
I can agree with most of the post. I have some middle guns the kral and one high end the priest 2. In 500 rounds I went to town on my krals, and aesthetics wise yeah they don't match ur 1k plus guns, but shooting wise I would easily put them to the test. The 22 is spot on out to 100 yards, and the 25 is sub moa at 100 yards. The priest, ok it's a performance gun and in both 22 and 25 caliber it's a tack driver, the CZ barrel is damn good. In 250 rounds I adjusted this to get what I needed and so far have been very pleased. I am looking to 3d print some external parts like a butt rest etc. Good luck. 
 
Totally agree. See what your gun is capable of after a break-in period. Have to let all parts "mesh" & settle in. Seems to me to be the best way to get a baseline for the gun's feel, function, accuracy, etc. I used to watch videos of my then current "gun du jour" & expect it to shoot as it did in the video immediately. Glad I learned to be patient & let whatever gun it was at the time show me what it could do after "settling".
 
I have 4 high end guns, including impact x on steroids, just picked up a taipan veteran long in. 25 shooting 29 gr neilson slugs at 975 fps, shooting starlings at 161 yds this afternoon over and over like super easy, my mind has been blown everytime I shoot these guns, my buddies were in complete shock to see a target that small get taken out at that range, just unbelievable
 
As SeattleDude said...

I'm also an (retired) Aerospace Engineer. I am though, new to PCP weapons, not powder weapons.

That said, with trigger pulls measured mostly in ounces or "maybe"...upward of a pound, and the VERY little actual movement of the trigger parts (from the trigger to the sear), there is scant little to break in. The air flow...yea sure, there's break-in there..! Soft lead pellets traveling down a barrel with very little heat (a small amount of friction heat) pushing the pellet...again little to no break-in there. The hammer and valve parts, yea, maybe a little break-in there, depending on the original design clearances.

So...where is this mysterious break-in taking place ?

Mike
 
As SeattleDude said...

I'm also an (retired) Aerospace Engineer. I am though, new to PCP weapons, not powder weapons.

That said, with trigger pulls measured mostly in ounces or "maybe"...upward of a pound, and the VERY little actual movement of the trigger parts (from the trigger to the sear), there is scant little to break in. The air flow...yea sure, there's break-in there..! Soft lead pellets traveling down a barrel with very little heat (a small amount of friction heat) pushing the pellet...again little to no break-in there. The hammer and valve parts, yea, maybe a little break-in there, depending on the original design clearances.

So...where is this mysterious break-in taking place ?

Mike


The barrel. As with all rifled barrels, each one is a bit different. Unless it is a custom job that has been hand lapped, some will need to be shot to finalize a fire lapping process. A typical barrel will shoot best with a certain amount of lead deposited in it, rather than squeaky clean. I think this is about the only break in that some rifles need. Some low-to-mid grade rifles will have trigger/hammer bearing surfaces that are not well polished, and some break in might help them, although in most cases they should be removed and polished. I've heard folks say that a tin of pellets should be shot before doing any fine tuning. That may be, but I've never had a rifle that needed that kind of lengthy "break in". I suspect the ones that do, have an issue that could be addressed without that much shooting.