As I understand the powder, Trail Boss can be loaded to maximum is about any ctg. case, using a full case to the bottom of the seated bullet - no compression - according to Hodgdon, who owns and sells IMR powders. 70% of the full case charge (no compression) is a starting load.

An example of how much powder it takes to fill a case is

Thus any .416 ctg. can shoot cast or jacketed bullets with Trail Boss - a very light weight, bulky powder.

The velocities developed are 'squib-type' loads with most cast bullets and ctgs. in the 900fps to 1,300fps range. Larger cases develope higher speeds, ie: a .416 Rigby would probably develop higher speeds than a .416 Taylor, merely due to it's greater capacity.

In the larger case to bore size ratios (.300 mags w/jacketed), you could expect speeds up to about 1,800 with max. loads. The pressures generated are very low for bolt actioned rounds.

The real plus with this powder is it's ease of loading, low report and light recoil. In many guns, it shoots with amazing accuracy using lead or jacketed bullets.

My .375 Wildcat generated 1,345fps with a 310gr. FN bullet and produced 1 1/2" accuracy at 100 meters. Loading was as simple as holding a bullet against the side of the case to see the level of the bullet's base against the side of the ctg, then dumping enough powder to come to that level then seating a plain based bullet - done. These shot right on the scope's 300 yard zero line - Burris scope. Seems to me the case held only 18 to 20 gr. of TB powder. It's an 80gr. water capacity case. A .45/70 case holds around 16gr. with 385gr. bullets.

My .17AH held 3.7gr. and put 25gr. Hornady HP's out at 1,785fp. giving 3/8" groups at 50 yards and striking right on the 'plex' reticle, scope set at 12X.