XCR break-in period

Congrats on the Rifle. Hope you enjoy it.

I only did a 3 mag (90 round) break-in. I think the break-in was done with the first mag. Had a few short stroke malfunctions and failures to extract in the first mag. Then no malfunctions in the next two mags. Since then I run it on setting 3 with Winchester ammo, setting 1 while suppressed and I rarely have any issues. The XCR seems to be a bit pickier with ammo than most ARs. If you use crappy steel cased ammo make sure to open up that gas port. If you use higher spec stuff; or fire suppressed, close it off.

I own a LOT of XCRs.....they've either all worked out of the box from round one....or several hundred rounds later, still had issues. I'm sure the parts wearing together and 'breaking in' is happening in the first few hundred rounds....I've just never really had the 'break in' fix an issue with a gun that wasn't working. YMMV.

Sean pretty well covered it, additioally a lot of rifle break in (especially with regard to precision platforms) is 100% hoodoo. The parts mate in the first couple mags. Occasionally, you can see accuracy tighten up in the first XXX number of rounds.

Another thing to keep in mind is that "run better" is kind of an invisible point on the spectrum...not that it's canon but for this one, it's binary. Rifle runs or rifle doesn't, if a rifle is hiccupping every 100 rounds or so, that's in the "rifle doesn't" category and needs addressing. Occasionally (as we've learned) suppressor choice and barrel length can effect this, so there is some fine tuning applicable to the operators unique setup. If your rifle can chew up 500+ rounds of your chosen ammo, you're gtg.