If you don't care about times you can use anything you wish, even a bolt action or a single shot. But you won't be competitive. For that you really want a semi-auto.
Here's my thinking, and the thinking of many other people on the ultimate SC rifle.
The theory is that the less muzzle mass the better. So you'll see attempts to get that done by various means, carbon fiber barrels, even a SBR length barrel with a tube permanently welded to it to make it >16" and thus federally legal w/o the $200 tax. Also legal in states that aren't free. But simplifying all of those attempts down to what they are actually trying to accomplish leaves one with a SBR (short barreled rifle). But that means paying a $200 tax to ATF. It also has other restrictions. But despite the restrictions that's the route I took. But I didn't intend to make a great SC rifle. I started out with the goal of making the smallest packable rifle possible. I tested the idea out with an arm brace. I liked the idea, but really disliked the arm brace. But I learned enough to know that I wanted to build the SBR version. So I paid my $200 and waited for ATF to send me my tax stamp. Then I bought the parts. I had 6 months to research the parts before the tax stamp arrived.
First test build w/ arm brace. The base firearm was a Ruger Charger Takedown (handgun). As a braced handgun it wasn't usable in SC.
In testing the above build I found that it would work but really disliked the arm brace. But I had what I needed for data and decided to move on with the build.
At some point in the build I found accuracy to be disappointing but realized that it would make a pretty nice SC rifle (RFRO). So while I met my goal of a small packable rifle I switched lanes and decided to use it where accuracy wasn't required and started to use it for SC. Here it was as I used it at the time.
But the I didn't forget the design goal. I needed to fix the accuracy issue and I wanted to make it smaller. So I got an 8" TacSol barrel that fixed the accuracy and also dropped the weight while making it smaller. The GI pistol grip came off and a folding grip went on. The buttstock changed a few times and for awhile much lighter arm brace went onto it. That was still legal for SC because the firearm itself is a rifle thanks to the $200 tax paid for it to be registered as a SBR. It finally morphed into this. It's short, light, and fast handling since it has no muzzle mass. It has no "holding" qualities for position shooting but I knew what I was building from day one. Accuracy isn't a priority but it's a tackdriver.
For SC the red dot goes on. The stock folds as does the pistol grip.
OK, I mentioned restrictions for a SBR. There are states where I can't take it. But for me that's not an issue. I stay in my state. But if I want to take it into a state that does allow them I need to inform ATF a week or so before making that move. There's paperwork that needs to be filled out. Once I manufactured the SBR it will ALWAYS be a SBR. There's no turning it back into a handgun as far as ATF is concerned. But on a positive note, I can do anything I want to it as far as configuration. I think I can even remove the stock entirely and just is it as a handgun and I'm good. But as far as the paperwork goes it's a SBR.
Not a restriction for me, but for others... When fellow squad member guns don't run as they should I have offered to let them use my SBR. I have yet to have any takers. One gent told me, "I'm afraid I'd shoot my finger off. ". I absolutely understand that concern. I've been using SBRs for many years but for a noob, yeah I get it.
But what do folks use for SC that don't want carbon fiber barrels or go through what I did? The rifles I see the most of are 10/22 types, Ruger and clones. They run and they're relatively inexpensive. Once moving they work fine. But the muzzle mass will slightly slow them down with a change of direction and every stage has at least one of those. The key to a good rimfire SC rifle is reliability. Great accuracy is NOT a requirement. I used my SBR for a few years before deciding I wanted better accuracy than I was getting. But it never held me back in SC.
Since a 2nd gun is only an additional $5 I also use a handgun. OK, I drive an hour one way to get to the match and we shoot 5 stages. If I'm having a good day that means approx' a minute of actual shooting for one gun. So yeah, another $5 and a second gun makes sense. After I started doing that it made sense for lots of other folks too. I was shooting a Browning Buckmark (RFPO) with a red dot sight. But I didn't like the grip angle. It's retired now and I shoot a KelTec CP33 with extended mags that hold 50 rounds. I shoot it cheeked. But it's definitely NOT old school. I have never seen anyone do it, but there's no reason someone couldn't shoot a SA revolver if they wanted to. I doubt that it would be competitive but I'd like to see it done.
