IMR Trail Boss Powder

[Bad Flynch]

Got my first plastic container of IMR Trail Boss Powder and tried some in two .45 Colt revolvers and a .45 Colt rifle. Testing was done at short range into a plain dirt bank. Accuracy above a general impression was not assessed, due to a lack of facilities. The stuff looks like a bottle full of teeny Cheerios and is very bulky.

My first trial was with Starline cases, Winchester standard primers, and Meister 200 grain bullets sized .454 inch. The first load tried was the listed minimum (5.5 grains) from data take from the IMR website. This light load shot like a dream in a Cimarron SAA with a 5&1/2 inch barrel and in a Ruger Original Vaquero with a 4&5/8" barrel. Like most light .45 Colt loads, it did not seal the breech well, but made up for that by burning cleanly, leaving essentially no unburnt powder and only light amounts of powder residue--even with this, the lightest load. This same load in a 1873 Uberti/Cimarron Winchester replica did not seal the breech well, either, and light amounts of gas from the breech could be felt as a round was fired.

Heavier loads to follow tomorrow. There is only one grain of powder difference between the lightest recommended load and the heaviest recommended load.

The only real problem encountered is that of metering in my measures. The 5.5 grain powder charge filled about half of a .45 Colt case and took up most of the available metering capacity of my Redding measure with the pistol metering chamber. I could not get the Redding to meter the maximum load, 6.5 grains, with the small chamber. About 1 out of 6 charges would be unacceptably light when thrown with the Redding, some by quite a bit. Perhaps that indicates bridging in the measure. When I switched to a Harrell measure, measuring was very erratic, and I eventually gave up and went back to the Redding, but with the larger rifle metering chamber installed. The Redding measure with the larger chamber would maintain about +/- one graduation on the end of the beam from charge to charge. Tapping the powder measure at seemingly appropriate times during measuring did not seem to improve the uniformity of the throws. I am going to guess that this powder, which is essentially a flake powder with a central hole, will be like metering shotgun flake powders. Perhaps the constant mechanical jiggling of a progressive press, like that of a shotgun progressive machine, will help even out the powder measuring situation.

General impression: decent stuff, but weigh charges until you can prove that your mechanical metering methods are sound. The sealing of the breech in .45 Colt rifles is characteristic of the fifles, not the powder. I have tried at least 8 or 9 powders trying to solve that problem and so far Holy Black is the best solution.

[Four-Eyed Buck]

BF, I think you'll find that the straight drop type measures will work better with this powder. IE: Dillon's, Lee's( disk types).Most of the reporters using these brands are stating that the drops are quite uniform. I've done some chronying in three calibers so far and posted the results on TOB and TFS. This powder loks very promising.......Buck

[Hemlock Mike]

I'd like to try it -- How much does it cost beings there's only about a half pound in the bottle.
I'm guessing that $6 to $8 should be about right.

Mike

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[Four-Eyed Buck]

Mike, I wish. There's 9oz. in a bottle, and it's averaging $11.50- $12.50 a bottle. Cheaper than VV- N-320 around here, but still not bargain basement.
 Still the performance verses the ones I'm currently using and the safety factor, IE: double charges, makes it quite attractive......Buck

[Throckmorton]

I asked a local 'big box' store to get some,and when I mentioned that I'd read of prices being in the 12.50 range he went all purple and blue in the face.
Could be why he called the next day and said he could't get any. 
I don't want to have to order it online but it NOBODY IN PORTLAND,OR  gets iit,then  Plan B will move up to Plan A's spot.
I sure would like to try it soon.

[Book Miser]

Buck,

If double-charges are the worst thing you're worried about, it's easier to install some kinda powder check on your press.

I load on a (don't throw rocks) Lee Loadmaster. I don't decap or prime cases on it, for reasons not pertinent here. But since it has a five hole turret and I was using only three, it was easy enough to install a RCBS lock-out die right after the powder drop. I like that setup better than Dillon's powder check, because it doesn't need a battery, and doesn't come from Mike Dillon. Bought mine second-hand from Church Key, but I don't think RCBS charges more'n $30 for the die, and it works on all calibers, detects no-drop or double-drop conditions just fine.

I shoot .38 in guns chambered for .357. Been loadin' on the light side, because I didn't have access to a chrony until recently. Under those circumstances, Trail Boss would have an advantage, in that you wouldn't have the ignition problems that can come with small powder volumes. However, I'm planning to step up to something that will drive a 158 grainer to pretty near the SASS maximum, because with the light loads there's not enough upset of the bullet base, and WAY too much lead gets left inside the guns.

Trail Boss will need to offer something pretty spectacular to get me away from Unique or Universal.

[Four-Eyed Buck]

Three grain charge under a 154g Bonus bullet leaves maybe a quarter inch space left in the case. Not much room for powder migration there, avg. speed 693.8 fps, ES was 35.56, SD was 9.16!!! Group size at CAS distance was about 1 1/2". This was in an older Cimarron SAA 5 1/2" .357. This stuff does work......Buck

[Big John Denny]

I loaded up 50 rounds of my 45 Colt shells with Trail Boss last Thursday to shoot them against my usual load of Win 231. The Trail Boss did fill up more of the case as noted in the other posts. I loaded 5.6 grains of TB in 50 and 5.6 gr of 231 in 50.

In my two 4 3/4" ROV I did not see any significant advantage in accuracy with the Trail Boss over the 231.

In my 1866 rifle I did notice the Trail Boss loads grouped in the center of the target, while the 231 loads grouped to the left about 2" away. This is a difference, but at the ranges we shoot rifles, I don't know if its enough for me to change powders.

I don't have a problem with double charges of powder because I check every shell before I move the shell plate. I don't weigh each charge, but I do weigh every 20th charge to insure everything is still as originally set.

My overall opinion, don't see a real pressing need for me to change my standard powder just yet.

[Four-Eyed Buck]

Big John, I did some chrony work with TB in .45's, matched against HP-38( same as 231). ran both powders through as a sorta check against.HP-38 at 6.0g with a 200g RNFP...Lo-504.4....Hi- 583.7.....Avg.-548.5...ES- 78.72....SD- 30.75. TB at .5.5g....Lo- 621.5...Hi- 672.1....Avg.- 655......ES- 50.60....SD- 20.61. TB at5.6g, Lo- 607.7......Hi- 698.4....Avg,- 640.0.....ES- 90.67.....SD- 24.75. These were shot from a 5 1/2" NRV with the chrony at 5ft from the bench. First set were 5 shot strings, the last set was a 10 shot string. Both TB strings grouped approx. 2" at CAS distance. Chronywise the TB performed a heck of a lot better than my usual load of HP-38. It fills cases better, seems to be more consistent than most of the powders I've been using. i've got some targets here that are pretty telling as far as accuracy at CAS distances is concerned. I feel, IMHO, that this a real winner and is gonna be a big seller for IMR...........Buck

[Cherokee Charlie]

I am only testing.

[Hemlock Mike]

I use my faithful Dillon 550B AND I stand up while I load so I can look into each case.  If I can just see that Unique in there, the load is OK.  Little to chance with my loading.

Mike

[Book Miser]

That's my point, Hemlock.

Any new gunpowder will have to prove itself worth my time in terms of something other than eliminating the possibility of double-drops. I use the lock-out die, I double check every few rounds with a little checking dowel, and I weigh charges every now and again while loading. Likewise, I decap and re-prime cases entirely separately from reloading them. This means I can poop out only about 200 rounds an hour, but that's acceptable.

So I am happy to see the chrony data on Trail Boss; consistent velocity numbers would be important to me, and I want to hear more about whether people find the stuff burns completely, at a number of different load levels. (My chief complaint about Universal is that I find myself cleaning up so much unburnt powder.)

Bottom line: keep those test results coming, fellers.

[Bad Flynch]

Well, I finally got around to trying heavier bullets. The conditions were all the same as before except for that one variable; I used Meister 250 grain FPRN bullets for this test. My load was 5.5 grains of Trail Boss, which is 0.3 grains short of maximum for that bullet weight according to IMR.

The loads shot well, generally to the point of aim, and produced no significant leading. The "no significant leading" is always a plus factor, but these revolvers are set up with 0.453 inch cylinder throats and the bullets are 0.454 inch. That means that a good tight fit helps prevent leading.

The loads, which should be close to maximum pressure, still did not seal the breech well. I had taken care to hand polish the cases so that I could accurately tell after firing. Even so, the amount of blowback was small and relatively clean. There was not a trace of unburnt powder anywhere and case and primer pocket residues were within normal limits.

I have cured the metering problem, apparently, by using the rifle metering chamber in my Redding measure. It seems to be able to hold +/- one graduation on the end of the beam without any difficulty.  I might mention that I use the same powder level check as BJD, and have for over 40 years; it is the way that I was trained when young. When setting up a measure for volume throwing, I calibrate it by weighing 10 throws and dividing, of course, by 10 to get the average.

I paid $12.57 for the 9 ounce bottle of powder, that figures out to $22.34 per pound. It is a little pricey at that, but it also represents a special effort by a company to fill a market niche. Somebody paid attention to us for a change.

[Cuts Crooked]

Yo Flynch!!!! That problem with the cases not sealing the chambers? (very common in .45s) I think I've finally found the Penultimate Solution ! Do you savy annealing? If so it works better than anything I've ever tried. By annealing the "neck" area of the .45 cases I no longer get any blowback in my Rossi! It's time consuming to do the annealing, but once done I don't have to worry about it again unless I buy a new batch of cases!

[Bad Flynch]

To Cuts Crooked:

I have run across that fix before, and the fellow who suggested it also suggested that annealing in a lead bath was the easiest way to go. I have no quarrel with the logic of it, but using W-W cases and black powder have helped. I still have a pair of .45 Colt Old Vaqueros and a '71 Win replica Cimarron that I can try it in if the mood hits me. Right now, I am bent on converting my 1894CBC from .45 Colt to .38-40 and using that recent pair of Old Vaqueros that I bought in .38-40. Besides that, I like the light bullets in that 40 caliber number. Anyhow, thanks for the suggestion, I appreciate the thought.

[Book Miser]

I'll start a stand-alone thread on this subject, but while we're talking about reducing load volumes, has anyone had any experience with Pufflon? Saw it advertised in the business-card pages of Shoot! The stuff looks like it has possibilities for use in really light loadings, but requires an extra step to load, and is said to work best when compressed.

I have been attempting to work up some real "powderpuff" loads in .38 special, for use with new shooters. My thinking is that you take someone who is new to firearms and start them off on a SA revolver using loads that produce a minimum of recoil and muzzle blast, then work them up to more usable loads. Something like the way one would gun-train a bird dog.

The problem with very light loads I've found is unreliable ignition. I had loaded some .38 brass with 158 gr copperclad wadcutters, over 2.7 grains of Unique. When they would fire, you could actually bounce a bullet off a heavy paper target at 7 yards. So we know the lower-limit; I think anything lighter would produce a large percentage of squibs, even with wadding of some type.

Any thoughts?

[Bad Flynch]

B.M.:  Years ago, when competing in double action revolver shooting, I experimented with light target loads. Some of those experiments were aimed at developing loads that were just barely powerful enuff to get a bullet out of my Python's barrel reliably. I eventually settled on PB for a powder because of a decided accuracy advantage with light loads. All loads were with various 148 gr HBWCs. You could probably have walked down to the target with the bullets.

I came to the conclusion that the powder makes a difference and that Bullseye and PB were supreme in the ultralight category, giving reliable ignition even with teeny charges. I always used Remington 1&1/2 primers because they were the softest cups for use with a lightly sprung revolver and they were mild in ignition capability. I ended up with 2.55 grains of PB in those loads and they shoot well even today. Love those Pythons.

A friend of mine shot a .32 H&R Magnum Dan Wesson. His charges of Bullseye were even lighter and it shot well with the little 32 caliber HBWCs. I am unable to remember the charge at this late date, but it would have surprised you how light the charge was and the recoil was nil.

[Book Miser]

...and you didn't have sporadic ignition problems without a filler or wad?

Forgive my ignorance, but I'm not familiar with "PB."
 

[Bad Flynch]

B.M.: PB is an older powder from the IMR line. It is useful in shotgun and light handgun loads, generally. If I have my information correct, the PB stands for Porous Base. It is an older flake powder whose burning rate is regulated by making the flakes porous. The manufacturing process for making those flakes made it more expensive than competing powders for years, then it disappeared for a short while. Now, as I understand it, it is back because a new process that saves money in manufacturing has been found, perhaps making it competitive in price. I have never found any ignition problems with small charges and have never used any fillers, despite the theoretical considerations that using a filler might be needed for those loads. I use fillers elsewhere, though. Hope that is a help.

[Book Miser]

Indeed it is a help. Thanks.

This is a project that I've had the chance to work on very intermittently. Without a chrony, there was no measurable data, and I hope I have saved notes on some of the lighter loadings. A few months back, I bought a chronograph, sharing the expense with Lady Law. Neither of us has had the opportunity to use it, but I've saved samples of some loads. The main roadblock is penetrating the user's manual, which is very poorly written and overly complicated.

Of course, the muzzle velocity data is only part of the problem. There appear to be no convenient measures of muzzle blast and felt recoil. It might be possible to capture sound pressure level data, at the same time the chrony data is taken. But I doubt that any sound level meter I can afford will accurately and consistently measure gunshots. To do that correctly, you'd need to take into account the rise-time of the pressure wave, which I'm sure the cheap meters don't do. They are intended to give data on steady-state noise, rather than impulse noise, and even at that, there's lots of room for operator error. I worked briefly in the sound measurement field, just enough to know it is easy to take data, but quite difficult to take meaningful data.

I suppose I'll end up asking someone else to shoot some of each load, and rate the relative recoil and blast on a one-to-five scale.