piston gun with barrel problem

[roughboy]

My barrel have a factory problem, inside the galvanized steel barrel theres tiny chunks of steel,from the inside tip to all the way through the barrel, this problem is causing the ammo (Marbles) to fit very very tightly causing it to jam.by the way my barrel is 1/2''x30''long. i've tried those marbles on a 1/2'' 2''long steel pipe,exactly the same width as the 30''long barrel except for the lenth (2''longto30''long) and it fits perfectly,so i know the problem is not the marbles.I've tried to go back to the hardware to exchange but they've ran out of stock.and no, i don't want to use pvc sch 40 or 80 i want to have a all steel rifle. i've tried to sand paper the inner barrel but the barrel is too long, (30'') please help what can i do? Thanks!!

[mark.f]

Try 1/2" type M copper tubing. It's a tight fit so some marbles may not work.

If you want a slightly looser fit, maybe you can try to go with 1/2" EMT tubing, used to carry wires. I have no clue as to connect this to your gun via a pressure rated adapter, (the adapters used in electrical connections are sieve-like cheap stamped-steel compression fittings), but you could most definitely measure the outside diameter and buy a suitable pressure rated brass compression adapter.

The pipe you have most probably only has just a relatively thick weld seam. All 1/2" SCH-40 steel pipe I've used, marbles rolled down past the seam.

[roughboy]

thanx!! i'll try the copper