Save yourself lots of pain and cash by not chambering anything in a 45-110.
Many have learned the hard way and rebarreled, or rechambered or sold their rifle at a loss to rid themselves of such a caliber.

I've been shooting 45-110 for a couple of years now and really like the caliber with 480, 500, or 535gr bullets and BP. I know folks that have been unhappy with 45-120 but not any shooting 45-110. The only issue I can imagine would be case length. To get a loaded 2 7/8s inch case in a roller may require modification of the hammer nose. Navy Arms sold italian rollers in the late 1970s, early 80's that were chambered for the 3 inch case and the hammer noses were modified.

I would strenuously recommend against smokeless in this caliber so no need to worry about strength, just have a reputable company like  Turnbull or signal mountain do the color case hardening for you once the action and barrel have been fitted and finished and the stock work completed. 

SS

BTW: with equivalent barrels rollers tend to be a bit lighter than Sharps rifles. My 45-110 is a 15lb Sharps with a shotgun butt. Recoil is still stout, recommend you build your gun with a shotgun butt...

SS

Track of the Wolf sells two buttplates I've used previously that will really help distribute the recoil on a heavy caliber:
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I've got the 2nd one (Sharps repro) on one of my Roller rebuilds and it's a very nice plate. Have the English style on a Hepburn, and like it as well.

(You need to Login or Register to view media files and links) Could this work in a RB?

There has been only 1 black powder cartridge rifle that I didn't like shooting. It was a LoneStar roller, in the silhouette configuration, ie: pistol grip stock, double sets, actually a heavy enough barrel, in 45-90.  I fired that gun 1 (once, uno, one) time and it hurt. The stock comb was not high enough for me to get on the stock right.  I have  a couple 45-110's, a couple 45-100's a 45-90 in Sharps and CPA configurations and they are all pleasant rifles to shoot. 

There was just something about the geometry of that roller that didn't fit.  That is why I suggested the highest comb possible and configured to get the rifle recoiling straight back. 

Here is another source of stocks

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Once you get that rifle built, it will make a great gong match rifle. That is where the 110 really shines. The long range shoots. (or as a hunting gun, but then you configure it different/lighter and you don't shoot it often as that wouldn't be fun).  

The 45-110 is really made for 2 things. Sitting on a hillside knocking off bison (which was ruined for us present day folks well over a 100 years ago) OR sitting/firing prone on a firing line shooting at targets 1000 yards away. There is also the matches at Lodi Wisconsin, in which case the rifle and sights can't weigh more than 15 lbs unloaded

Here is a site about long range shooting to check out

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Here is a match to think about in the future after you have the rifle built

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