1. For a .45 LRML, your barrel should be made from 4140, octagon to round. 1-1/8" at the rear tapering to 15/16 at the muzzle. It must be that rear dimension to withstand the chamber pressures of a 550 grain bullet behind 90 to 100 gr of powder. The Rod England breechplug is required as it is correctly made to withstand those pressures. the ones sold by TOTW and others are suspect.
2. The barrel is 36" long so the distance between the front and rear sights is that length. That gives you 1 MOA, which is what the calibration of the rear sight is. The barrel needs to have a recessed crown.
3. You will need a platinum lined nipple properly fitted to your breechplug. A conventional nipple will burn out in as little as 10 shots.
4. You will need a proper bullet mold sized to your bore. Then you will need a bullet sizer that is approximately .001 under your bore size. The bullet should be a slip fit and load with only the weight of the ramrod. A lubrisizer is ideal as it both lubes and sizes the bullets at the same time.
5. You will need a drop tube for loading. You will need a scale marked in grains to weigh your powder charges and vials to keep the powder in. You will also need to weigh your bullets so they are +/- 1 grain. Over and under weight bullets can be used but must be segregated into groups by weight. These bullets will require a sight adjustment, but are good for sighting in and getting on target.
6. You will need a spotting scope to see where they are hitting and preferably a spotter helping you who can see where they hit for adjustments.
7. You will need a machinist to mount your front and rear sights so they are centered on the bore. This ain't a hacksaw job.
Rod England's complete kit will run around $1400. Figure another $150-200 for mold and sizer. Good front and rear sights will run upwards of $800. Cheap sights won't get it done. Platinum nipple is $50.
8. You can build a cheaper rifle using a Green Mountain black powder cartridge barrel in one inch octagon if it's .38 or .40 caliber and be able to use a TOTW breechplug and other parts sold by them. You'll still need most of the other stuff. Some of the parts can be sourced from Pecatonica which they use on their Rigby kit.
This is a .38 that I made 2 years ago. It shoots well out to 500 meters but probably not much further. However, it doesn't give you a concussion every time you shoot it. .45's will kick the snot out of you. Snapper can probably add additional info.
