Speaking for experience & personal observations, if you are purchasing the rifle to shoot NRA-sanctioned silhouette, a .45-2.1” (AKA .45-70) is more than enough rifle to do the job. A rifle w/ a shotgun butt will be more comfortable to shoot.
I shoot an approx. 14 pound Borchardt, .45-2 7/8” (AKA .45-110) & after about 30 rounds, it gets tiring. I can shoot my Sharps .45-2.4” (AKA .45-90) for longer periods, but I “dunno” if I’d want to shoot it for a silhouette match due to the recoil. My .45-2.1” rifles are more pleasant to shoot. After you start shooting chamberings bigger than the .45-2.1” & the .45-2.4”, the effects of recoil become more noticeable.
Also it is relatively easy to develop a White/Nitro Powder (AKA Smokeless) load for the .45-2.1” should you want. Not saying that it can’t be done w/ the bigger .45s, but you really must know what you are doing & be very careful when loading – really easy to drop a double charge in those big cases & w/ wads or fillers, it is easy to ring the chamber. I once saw an all-original .45-110 Borchardt chamber rung on the second round w/ White Powder.
Even thought I don’t shoot silhouette, I attend the matches @ the local club. I have yet to see a target not topple when hit solidly w/ a .45-2.1” & a 500 grain bullet, or a .40-65 & a heavy bullet.
A .40-65 is a real sweet caliber to shoot: little recoil & economical as far as bullets, powder, & brass. First time I shot mine, I wondered if it went off. It’s a far different round than the bigger .45s.
A rifle of silhouette weight & chambered in the .45-3.25” case (AKA .45-120) will be very uncomfortable shoot, esp. in the prone position & even more so if it has a crescent butt stock. Several years ago, I once shot one about 3-4 times & handed it back to the owner. There was a reason why he was selling it—“way too much gun”, even w/ a 500 grain bullet.
If you look over prior match silhouette equipment lists & winners circle, you’ll see that the .45-2.1”, .45-2.4”, & the .40-65 are well represented. The bigger .45s really "shine" at the Long Range matches (800, 900, & 1000 yds).
Any barrel can be cut back to help reduce weight. Just make sure that whoever does it knows what’s he’s doing & is careful w/ the crown.
The NRA-sanctioned silhouette 12 pound, 2 oz weight limit includes iron sights; 15 pounds limit w/ a 'scope. NRA-sanction BP target/LR match weight limit is 15 pounds (inc. scope or iron sights)
