Trail Boss for lapping loads?

[Abert Rim]

Got some lapping bullets for my Marlin .45-70 and the caster told me to use about three grains of Bullseye to push them through the barrel. Checked my stash and I am out of Bullseye, and don't particularly need a pound, even if I could get one. Has anyone used Trail Boss for this task in .45-70? How much? Any others subs?

[felix]

Albert, any amount of powder will work, provided you keep the powder on the primer hole. Use toilet paper, loosly wadded. Yeah, trail boss is OK. 4 grains? Make sure boolit comes out of barrel. Use a little more than you'd think for the first shot to get a feel of how much you really need. ... felix

[TREERAT]

felix, trail boss is very bulky for the weight, and quick powder. please ignore if you already know this! just my opinion - I would be scared to use a filler with it, I have talked to Hodgdon about loads with trail boss in Straight wall loads and was told I could put as much in as the case as it would hold - AS LONG AS THERE IS NO COMPRESSION - this conversation with hodgdon was concerning .460 S&W and .500 S&W + ranier plated ( loaded as cast bullets).

I am sure Albert is wanting low velocity to do his firelapping. even a max load of Trail Boss will still be low velocity.

To Albert: do you have any unique? I have used a lot of 10g unique loads in my 45-70 with cast and velocity is around 1,100 fps aprox. back when I still had my cronograph!

I am new here, an am sure felix knows much more than I do!!! however, I have never done fire lapping, so I do not know what velocity you are looking for. just thought you might find the above info useful.

[jdgabbard]

In an article (in handloader I believe) a while back they had a little brief talk about trail boss. The picture of the .38 spl case they were using was almost filled to the rim. And I'm almost positive that it would have been a compressed load. I doubt you'd need that much though.

Out of curiosity, why not just hand lap the bore??? Sure it takes longer, but from what I understand, the results are much better, without the over-wear on the barrel.

[stubshaft]

The velocity of a lapping load should not exceed 750fps. The object is to have the bullet just exit the bore without any possibility of leading. Trail Boss has a narrow range and can peak rapidly. I use only 14gr in a 500 S&W w/400gr bullet(alot of airspace in this case). It has not shown a propensity for detonation like reduced charges of BE. I would start with 5gr. and no filler .