Quackenbush Outlaw .457 Long Action - Part 2
by B.B. Pelletier
Today, I'll share the power and accuracy I've achieved thus far with my .457 Outlaw Long Action. Before that, though, we'll look at what the rifle was doing with the original 25" barrel. I had to shoot several bullets to find the right one for that barrel, too. I went through five different styles, lengths and weights before settling on a 330-grain bullet recommended by Randy Mitchell. Here's a phenomenon I noted. The second shot always went several inches above and to the left of the first shot. I've seen that phenomenon before with big bores - in fact, it seems common to me. With all the bullets I tested, I noted the first and second shots on the targets.
Sight-in was done at 50 yards, even though this rifle is accurate much farther. Eric Henderson, who hunts with a Quackenbush .308, regularly gets prairie dogs beyond 150 yards. Larger game is taken out to 100 yards pretty commonly. Most of the bullets I shot grouped inside 2 to 3 inches at 50 yards, but as I mentioned, first and second shots were several inches apart. Not to worry - there's a field expedient for that, after we find the right bullet.
Typical dispersal of an unsuitable bullet at 50 yards. Note that the three first shots all grouped lower than the second shots.
You might think 3,000 psi is the standard fill for all big bores, but there are no standards. In the past, I've tested certain Quackenbush rifles, only to have my reported velocities trumped mightily by someone else filling to a higher level. I use an 88 cubic-foot carbon fiber tank that holds a 4,500 psi charge, so it's no trouble to fill over 3,000. However, during the testing I did with the 25-inch barrel I was getting my tank filled at a local shop that was underfilling it by about 900 psi! That makes a HUGE difference in how high you can fill and also in how many shots you'll get from a tank. They charge $6 for a fill and I was only getting 20 shots before the tank pressure fell to 3,000.
Here are three first and second shots on a 3200 psi fill with a 440-grain lead bullet. The first shots are the tight group at the bottom. Too much dispersion on the second shot, though, for this bullet to be considered.
Since I was working the ideal fill pressure from the bottom up (that is, first 3,000 psi, then 3,200, then 3,400) and also testing many different bullets, I didn't get very far. I did confirm that my particular rifle likes a fill to at least 3,400 psi. By the time I discovered that, I could no longer fill that high. So, back to the shop for more air and try it again. I hadn't yet discovered what this shop was doing with the fill.
A different 400-grain bullet did this from the 25" barrel on 3200 psi. This is going toward the usable range, but we're not there yet.
On the second trip to the range, I was able to go to 3,400 psi right away, and there were only two bullets left to test. The last one (the 330-grainer) proved to be the best, Groups were under an inch at 50 yards. This bullet had the closest spread between the first and second shot groups. First-shot velocity was 791 f.p.s., and second shots were going 725. Shot one was producing 459 foot-pounds, and shot two made 385. That's great for game weighing under 300 lbs. However, just as I was getting close to sighting-in this rifle, other things intruded on my time and the rifle had to be set aside for a while.
The 330-grain bullet on 3400 psi from the 25" barrel showed some real promise.
During the time I wasn't shooting, Dennis said he had my 33" barrel ready, so he shipped it and I installed it. Then, Eric Henderson invited me on an exotic sheep hunt in central Texas. There were only a few days to get ready, and the weather wasn't cooperating, so I had to wait for a good day to sight in. Of course, all bets were off, now that the barrel was changed. I went back to the same paintball store I had been using and got another tank of air and when the one good day came, I went back to the range. Naturally I tried the same bullets as before, the bullets that worked well in the 25" barrel, only this time they were all over the place - as in missing by feet! I said three feet in the first report, but after examining the targets it was more like 14". I also tried a 330-grain bullet Dennis recommended, but it printed no better. There was no way I was going hunting with a rifle I couldn't trust to hit closer than 14" off my aimpoint at 50 yards!
I missed the hunt, but I also went to a different paintball store for the next fill, and the results were dramatically different! I'm now up to 28 shots on this fill and I'm still filling to 3,500 psi, which seems to be the optimum with my rifle. I tried all five of the bullets I'd been given, but nothing wanted to group as well in the longer barrel, so I slugged the bore. That means ramming a lead bullet or ball (balls are much easier) down the bore and measuring the diameter after it comes out. My bore measured 0.4585", which drove me to ask Dennis why he calls the rifle a .457. He says he should have called it a .458, which is far more common in black powder bullet sizes, but no matter to me. I already cast my own 412-grain .458 lead bullet for a .45/70 Trapdoor Springfield, so I took that back to the range. To my delight, it groups very well! Perhaps, it isn't the most accurate bullet for this rifle, but I would have no reservations about hunting with this one.
The first five bullets I tested on the left. The small one on the right of that group is the 330-grain that worked well in the 25" barrel. The group of two at the right is the 412-grain bullet that works best (so far) in the 33" barrel and another 350-grain copperplated lead bullet I have yet to try
This is a four-shot group of the 412-grain bullets. Four shots are not conclusive, but we seem to be headed in the right direction. I shifted the aimpoint of the duplex reticle between shots one and two to get this group. This group measures approximately 1.25" between centers.
Velocity on shot one is 783 f.p.s., and shot two goes 734 f.p.s. That's 561 foot-pounds on shot one and 493 on shot two. After shot two, the gun's pressure dropped from 3,400 to about 2,200 psi. This is ample power for the hunting I'll do. I plan to hunt deer, pigs, boar, exotic goats and sheep and anything else in that general weight range. Someone asked if I'd hunt a bear with this rifle, and the answer is "no." It's true a rifle like this could decimate a small 90-lb. honey bear, but I wouldn't trust it on anything larger - even a small black bear. Read Lewis & Clark's adventures shooting grizzlies with their .54 caliber rifles, and you'll see why I say that.
Dennis Quackenbush is working toward an air rifle with the muzzle energy of a .50/70 black powder round. That's a .50-caliber 425-grain bullet leaving the muzzle at around 1,200 f.p.s. (from a 32" Springfield barrel). That's 1,359 foot-pounds, and such rifles were very successful buffalo rifles in the 1870s, sometimes taking bison at ranges up to 500 yards. It's a lofty goal for an airgun maker, but I wouldn't bet against him.