A friend and I are having a disagreement over the wisdom of shooting without a Briley Slimline choke installed in the barrel.
I think it is unwise, and my friend went out and shot 150 rounds though his chokeless barrel.
Who is right?
As always, you are right. I am not familiar with the Briley “Slimline” choke, but if it is anything like their “Thinwall” custom choke for solid choke barrels, Briley cuts the threads with a wide, flat topped thread. Width gives it strength, while the flat top makes it thinner and thus suitable for using on solid choke guns. Factory choked guns use the standard sharp edged machine threads as they have more room.
Every time you “shoot threads” you whack those threads with the wad and often some shot. This is never good. At best it clogs the threads. At worst it can damage them. Clogged threads can cause some very subtle problems. As the threads fill up, when a choke is reinserted at a later time, the build-up in the threads might prevent it from being fully seated when it is screwed in. This will cause an increased gap between the choke skirt and barrel. This will build up with carbon and plastic as gas forces underneath the choke skirt. Under certain conditions this can force the skirt above the line of the bore. When this happens, you are going to add about an ounce or so of tubular stainless steel to your next load of shot as it exits the barrel. This happened regularly on an early screw choke version of one popular brand of Italian gun. It has since been corrected, but caused some very unpleasant surprises for a while.
Shooting threads is also not very productive as to time. Sure, you save time by not screwing in new chokes, but you will absolutely, positively have to clean those threads carefully at a later date. This takes more time than screwing in the proper chokes in the first place.
Also, without the thinline chokes in the gun to give the muzzles strength, the tips of the muzzles are VERY susceptible to dings and dents. The muzzles on my FNs threaded for the Briley Thinwalls are absolutely paper thin. I wouldn’t dream of using the gun without the added strength of the chokes. Factory screw choke guns have much more meat in the muzzle (hence the nose heavy balance that most of them suffer from) and so it might be safer to shoot threads, but why take the risk?
Screwing in a set of cylinder bore chokes really doesn’t take too long, especially using the most excellent Royal Wrench. If your pal is too cheap to buy a couple of cylinder bore chokes, then he is playing the wrong game. I use cylinder bore a great deal, but I do it with the proper chokes in place. I never do it with threads.
One final argument against shooting threads: No manufacturer that I am familiar with recommends the practice. I know that most people don’t bother to read the manuals that come with their guns, but it might be worth a moment or two of their time.
Shotgun Report’s Technoid
(Often in error, never in doubt.)