With my CZ (rimfire) target rifle I would clean every couple of weeks (so maybe 50 rounds of .22 target ammo).
If I didn't then I would need to fire a few 'warmers' to get the rifle to shoot to POA. Then I discovered C4.
By regular cleaning I could simply set the rifle up and fire a couple of sighters...just in case 'something' had been knocked or moved since the previous week.
The sighters were always sitting there at the POA...no actual warmers needed or time taken to fire shot after shot and watch as the bullet holes 'walk' their way into the target centre.
Now this is a rimfire, and they probably don't generate as much heat/carbon as a centrefire. I'm no scientist on this matter.
I only know what the results show me on the target.
My thoughts? A centrefire having 40 or 50 rounds through it will be developing a carbon ring already (plus hard carbon all through the bore). Not good for accuracy or the barrel.
Although most of you are only interested in 'minute of deer', and not trying to hit a 2mm dot at 25 yards.
Use C4 after every time you shoot? Yes, why not? Once you have the barrel clean why would anyone want to let a carbon ring develop again...and then spend more time getting it all clean again.
Although, to be fair the average hunter (centrefire)...maybe once or twice a year would probably be fine.
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