Re: Best 9mm or 45 acp pistol to suppress?
Two parts to your question, the first is almost impossible to answer without you knowing what you need as far as a host. The second is your question about the ability to "lock the slide." That is a rather unusual question on these threads. If it is your intent to eliminate mechanical noise on your new host thru lock-out, there are already a few givens. One, your shooting subsonic as there is no reasons to cancel the quieter mechanical noise if your going to create supersonic projectile signature. Secondly, your going to buy a top end quiet can. Some 9mm and .45 cans are just plain loud. Thirdly, you are hand cycling and are ok with that. 9mm should suppress more efficiently than .45. If that is your intent then you can go at eliminating mechanical noise a numbers of ways. First, is what you described, a lock-out on the host. Second, a lock-out on the can.
Slide locks on hosts are rare in their initial design, add-ons are more common and, for the most part, are hard on the frame. We see some attempts, here are a couple. Note-yes, that is a photo of one of the "never existed" Army issue, true semi automatic (not manual) Semmerling XLMs in .45acp. In other words, when you aren't in lock up on the XLM that micro .45 auto loaded! It still is the smallest .45 ACP automatic ever produced at 3.8" X 1".
Every one has an opinion on slide lock-outs, your asking, so mine is the two kits in production do work, but are the wrong way to go. Every one I have seen was made to work in a very limited operational environment. In other words, they have real detrimental effects on the frame/slide/rails. I've seen cracks, stretching/distortion and jams.
IMO, The right way is to lock out the can through proper tuning on the Neilson device. I wrote a piece a while back on "putting your can on its ears" essentially over riding the Neilson device by a quick twist of the wrist on some can designs. Those providers planned for this feature in the Neilson and the results leave the host frame alone. When one realizes that most can makers over-pressure their can to begin with to INSURE cycling (already a problem for some alloy frames) the right way to go is to TUNE the Neilson. If your maker can tune, usually through proper matching of host, rounds, suppressor and springs, you are done and have a great host that will last.
Good news and bad news. The bad news is that can lock-out requires a quality adjustable Neilson and tuning. That takes time and requires both having a broad spectrum of Neilson springs to choose from and using ammo within the tuned spec. Most can makers don't include lock-out as an option, and those that do will do the work for folks that actually need the requirement. The good news is that once its done, to go from auto to manual is 3 seconds. You should also know that the process favors steel frames (heavier slide weights) with 1911 frames in either 9mm or .45acp being most often seen.
Good luck.
P.S. if yo think a P22 with a Gemtech unit works great, you have some real positive experiences ahead of you.
