I've got a Mossberg 510 with the 18.5" barrel. Normally shoot TSS with a Trulock .585 and I happy with it, I like a more open pattern. I bought some 20-gauge LB #6 to shoot in the Fall to stretch out my TSS. The .585 is too open with the LB's, any suggestions on a choke or a range of constrictions to try. I know LB's aren't going to compare to the TSS.
Also what makes a Carlson LB choke different than another choke with the same constriction?
I'm working on a Mossberg Bantam 500 20ga with the 22" barrel during the winter. I have a Carlson's LB choke and a TruGlo Headbanger and a lot of LBXR #6s to try. When the weather gets better here I'll go to the bench and do some pattern testing and let you know the results. In my Remington 870 20ga with a 21" barrel the LBXR #6's shoot better with the Carlson's LB choke and I have tried about every choke I could find with it. It does "okay" with the #6's but it is a beast with TSS #9's and that Carlson's LB choke. My Stevens 301 20ga with a 22" barrel seems to shoot about any choke shell combo I've tried with very good hunting patterns. For being the cheapest 20ga shotgun I've bought in recent history it has been worth every penny.
As for your question...I have no idea what makes the Carlson's LB choke different but they have really performed in any brand shotgun I've shot with the LBXR ammo and I've tied a LOT of shotguns.