wth is blowby?

[flatblack]

i know what it is in a combustion chamber of an engine, but when it comes to rifles i have no idea.... basically im looking at buying a used 243 the guy says its used to be a deadly accurate rifle and scope set up but he said he shot it 2 years ago and it had blow-by. is this guy yankin my chain, and if there is such a thing is it an easy or expensive thing to fix?

[roger]

i assume that blowby is the neck of the cartridge having black stains on it after the shot.
if so...i dont THINK it matters, but a competant inspection of the chamber would be in order.
i would hope that the bbl has been cleaned properly over its lifetime..maybe its just so crudded up that the pressures are going thru the roof and the gases are having to escape however they can. after attending dick284's course on shooting, i suspect alot of people are not aware of the intricacys of cleaning a gun. everyones approach is different
depending on the damage to the chamber you may be able to salvage it by turning it into a AI version of a 243 or a 6mm. or just screw a new pipe on it.
but again, purchase price will dictate how much you spend/ effort / trouble you can donate to it.
a new gun is sometimes a smarter investment in the long run

[Cappy]

Getting carbon on the neck/shoulder area of cases is pretty normal. If it is excessive it is usually a result of a low pressure load being fired and the case isn't sealing up tight against the chamber.

If he is talking about gases coming up around the bolt then there are issues with the lock up of the bolt to the reciever and the rifle needs to be checked by a gunsmith.