Trailboss 308 loads - question

[IrvJr]

Hey guys - I looked on the Hodgdon website and got info on using Trailboss to make some reduced recoil 308 loads. I plan to load some up soon, and was wondering if anyone here has experience with reduced power loads using this powder.

If so, have you had better accuracy from your loads if you use the minimum recommended powder charge or something closer to the max load?

For 308 Win, Hogdon says that 10 gr of Trailboss with a 150gr Nosler bullet has a muzzle velocity of about 1176 fps. The max load of 14 gr of Trailboss has a muzzle velocity of 1417 fps.

I would like to get decent accuracy at 100 yards and under. Should I move towards the min load or the max load for the best accuracy? Would a faster load be more accurate due to the higher muzzle velocity (well above the speed of sound)?

Thanks.

 

[Ideal Tool]

Hello. IrvJr. First off, since it seems you are new to TrailBoss powder..If I were you, I would be more concerned with safety than with velocity at this point. While TrailBoss bulks up in a case..that doesn't mean that it is low powered like black powder..if you check it out on the burn chart..it's way up there with Bullseye. I would start out with 8 or 81/2gr. and load 3 of each going up .5gr. at a time, watching close for pressure signs. Remember..it's easy to add more powder...but when you pull a trigger on an overload..it's a bit too late. Best of luck!

 

[jinxer3006]

Actually, as long as you don't compress Trailboss, you really can't overload it in a rifle cartridge. So the 10 grain starting load should be plenty safe.

Back to you original question--I personally have only experimented a little bit with Trailboss so I can't back this up, but I have read elsewhere that Trailboss tends to do best with hotter loads--somewhere around 85-90% of max load if I remember correctly.

 

[Brian Pfleuger]

IMR plainly states that filling a rifle case, ANY rifle, all the way up to the base of the bullet is completely safe.

They recommend starting at 70% load and working up toward 100%, looking for accuracy not pressure problems.

I have used Trail Boss to fire form cases in 204 Ruger and 7mm-08. I have never exceeded about 75% loads because I only want enough pressure to form the case.

Trail Boss burns very clean and the accuracy with my 204 was plenty good, especially considering that I was not shooting for groups. I didn't shoot groups at all with the 7-08.

 

[Unclenick]

A full case won't run over about 35,000 psi. That's more than you want just for case forming, but I have seen one group posted that was fired using 150 grain Hornady FMJ's, and the 10 shots were inside about an inch.

 

[IrvJr]

Thanks guys. I guess I'll have to experiment (starting with the min load) and find out what works best in my rifle.

I thought the stouter loads might work better because the min load, which has a published velocity of 1176 FPS, leaves the barrel at just about the speed of sound. I'm wondering if accuracy might suffer if fired from a shorter barrel or at 100 yards due to the bullet crossing into the transonic realm (instead of staying supersonic).

Initially, I will be using my Ruger M77 (22" barrel) but eventually, I'd like to use these loads in a shorter (18.5 or 16.5 inches) barrel gun.

 

[Doodlebugger45]

Let us know how it turns out. I recall a gentleman on this forum was posting some info about the results he was getting with Trail Boss in a 30-06 and they were very good groups. I have thought about trying some slower loads for my .308 as well just for grins. I haven't done so yet, but I was thinking about playing around with H-4895 to find an accurate spot.

Higher velocities don't necessarily equate to better accuracy. It will all depend on the vibrations set up on the barrel caused by whatever pressures are generated and their duration. I know those long distance iron sight guys use .45-70's to hit targets out at 1000 yards, and those bullets are travelling at about half the speed of smell.

 

[IrvJr]

Thanks guys. I am going to pick up some primers and Trailboss powder this weekend. Unfortuanately, I have to wait till the ranges defrost a little (berms are frozen) before I'll be able to test my handloads out.

 

[Unclenick]

As far as transonic velocities go, I know the 168 grain Sierra MatchKing is very sensitive to this and can tumble. That's unusual though. I think, in general, you'll find flat base bullets are easier than boattails to get shooting accurately at closer ranges and in that transonic range because they are shorter, so the stability factor a given barrel twist provides will be higher for them at any given velocity. You don't need the higher BC's then anyway.

 

[IrvJr]

thanks Uncle Nick for the post!

After I develop some Trailboss loads, I plan on developing some H4895 reduced recoil loads for whitetail hunting, and then some full house loads for long distance shooting.