hollow base bullet / Trail Boss

[x_wrench]

Hi, i just bought a container of trail boss, and ordered a new (Lee 405g) hollow base bullet mold for my 45-70. i understand how to load normal flat base bullets with it, but i do not know if i need to do anything special due to the hollow base in the bullet. i will also be loading 38 special with lhbwc (purchased not cast), so the same question would apply with that. is this something i need to concern myself with? or just load like they were flat base bullets?

 

[Livin_Cincy]

You do not want to compress/ crush Trail Boss as it burns differently and makes an over charge possible.
The Published Loading Data is below the bullet base and may represent a "most accurate" charge.

IMR® TRAIL BOSS® REDUCED LOADS FOR RIFLE AND PISTOL
https://www.hodgdon.com/wp-content/uploads/2016/11/trail-boss-reduced-loads-r_p.pdf

 

[Walkalong]

or just load like they were flat base bullets?

That's what I would do. Load it up to the base.

 

[troy fairweather]

i think i was doing about 15 grains of tb in my 45/70 worked good.used the lee diper

 

[bobinoregon]

I load the Lee 405 hollow base and also a Lyman flat base and I treat both the same. I really doubt that the cavity is large enough volume to make any difference, but I also rarely ever use Trailboss in anything but my old saa pistol. We shoot a lot of those powder coated 405 hollow base through several different guns with good results.

 

[x_wrench]

thanks for the help guys. my mold just arrived, but i am feeling a bit under the weather today. hopefully i will get some bullets cast tomorrow. i will be shooting these out of a Marlin Guide Gun, that i had a muzzle brake installed onto. do you think the base will open up enough to contact the brake? i do not have a screw on thread protector, partly because the brake did not come with one, and because the brake sits under the front sight, i really had not considered removing it on any sort of regular basis. other than terrible accuracy, i am not sure of a way to make sure the skirt does not contact the brake. i really doubt that paint would hold up on the inside of the brake.

 

[bobinoregon]

I really can't imagine the base opening up enough to be a problem. I don't have muzzle brakes but shoot them in guide gun, rifle, and revolver. Its a fairly heavy wall on base

 

[x_wrench]

yes, i see that now. i cast up about 70 yesterday (figuring i will get 50 good ones or so), and the hollow base wall is heavier than i had anticipated. i found the actual trail boss data page, and tried loading up one round (none of the bullets are sized or lubed yet, so i just hand lubed one). i started seating the bullet to the 2nd groove from the top, and it was way to long. it would not even chamber. so i pushed it in to the top of the top groove, and it is still to long ( 2.617" ), which will chamber, but will NOT cycle thru the action. so now i have a problem i was not thinking about. as i see it, i have several choices. 1) hand load them one at a time into the chamber to shoot them. 2) shorten up some brass and keep it for exclusive use with these bullets and probably have to buy a second factory crimp die, and modify it for these rounds. and modify the load data for less case volume. 3) try to make up a jig to shorten the nose of the bullet after they are cast. or 4) have the mold cut down (which will make them a flat nose rather than a round nose)(and who knows what that will do for stability) so i can use them as cast. none of them seem like a great choice. well, as i am typing this i thought of one more possibility, seat them deeper, and try to get the factory crimp die to crimp further down on the case where there is a groove in the bullet. which will also reduce case volume, so modify the load data as well. i have no idea if i will be able to do that or not. i did think of just seating them @ 2.550" and crimping the bullet into the nose of the bullet. but being this has a tubular magazine, i am certain that would fail at the first firing. if not sooner. its ALWAYS something, isn't it?! grrrrr

 

[bobinoregon]

I seat mine here and it cycles in 2 different guide guns and two rifles

 

[x_wrench]

bob, that appears to be at the top groove in the bullet. which is where i set my first bullet, then crimped it. my O.A.L. came out to 2.616" which will not work in my Marlin. any chance you could put a caliper across that round to see just how long it is?

 

[bobinoregon]

I get 2.6205 and I just ran several through a newer guide gun thats still pretty stiff to cycle.

 

[x_wrench]

thanks bob. i tried a round that was 2.616", which will lock up my guide gun. so there must be a difference in our guns. i am going to look to see if i have any Hornady FTX rifle cases empty, and push a bullet into that (those cases are a little shorter). maybe that will make the round short enough to cycle.

 

[x_wrench]

well, after fiddling with the adjustments, i finally ( i had to get out the 5x glasses ) and got the standard length brass to work. but it is going to be a pain, as .003" is all the play i have before the gun will not cycle them. i did find my Hornady brass, and it works much better (meaning i don't have to mic every round). so that is what i am going to load for the most part. i took these out and shot them today. and i am a bit perplexed by the results. i dug out 5 of the 20 rounds i fired (that's all i could find), and of the 2 that are not deformed, both have a smaller base after being shot than they did when loaded.

 

[Englishmn]

How much smaller? ideally the whole bearing surface of bullet will be smaller and engraved from riflings.

I don't have a 45/70 but load the lee 457-405-f
Bullet in my 460 s&w with trail boss.
It should be shorter mine measure 1.024" than your hollow base and may be a better choice for your application plus its a double mold.