Earlier in April David Minshall published an article in the MLAGB's Black Powder magazine written by Bill Adams and myself regarding the Kerr barrel project. Bill covered the historical aspects. I wrote about the barrel project and its status as of the end of February.
http://www.mlagb.com/blackpowder/index.htm Click on the name of the article, “The Kerr Rifle Project”.
Things have moved along since then and the first repro Kerr barrel is under test by Bill Adams. It’s something he has to do as his time allows and he doesn’t have a lot of time to spare.
I sent the following report out to those on the Repro Kerr Barrel email list I keep for those who have expressed a serious interest in the barrel and have asked to be added to the list:
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"Attached is a report of yesterday's testing of the Kerr barrel. It has the potential to be extremely accurate... A more careful drilling of the flame passage and using a conical bottomed hole in the bolster would be a better system... [this is an easy fix].
With a lighter trigger pull, better sights, and a reworked ignition system, the Kerr will work well. The rifling seems to perform as expected. I will bore out the bottom of the nipple seat in the bolster...
From the report body:
"I had a variety of test bullets that consisted of short hollow based Lee trash can style bullets, .45 grease groove Lyman bullets in 475 grain and 500 grain weights, .45-70 hollow based bullets weighing 405 grains, 530 grain bullets cast in an original Whitworth mould, 530 grain cylindricals from a Confederate mould, and various other .45 bullets. All of the bullets were run through a .451 sizer, although those cast in original moulds were smaller than .451. Those have not yet been test fired.
The barrel is a tight .451, so the .451 bullets are almost a press fit and the longer bullets are quite dicey to load. There was no time to test paper patched bullets. Even if time was available, I stopped testing because I could not see the front sight post...
I fired only ten test shots. Five were from 50 yards using a very rudimentary rest, consisting of kneeling and resting my elbow on a toddler’s picnic table for the first five shots. The position was less than stable. The second five shots were fired off hand. From an accuracy viewpoint, the results were less than spectacular; however, they were not a total disappointment.
The first five shots were fired using 52 grains of 2f Swiss powder topped with WonderWads. The first shot was a .451 405 grain hollow based Lee bullet and it struck 3 1/2” low and 1 1/2” to the right of the aiming point. The second shot went about 2” high at 1 o’clock. The third shot went 2” high at about 12:15. The 4th shot was a heavier bullet that struck 1” high at 12. The 5th shot was a lightweight Lee trash can style bullet that hit 3” high at 12:15. If the target was a standard-sized N-SSA 50 yard target, the score would have been 40 out of a possible 50. The group was 2 1/4 “ by 1 ΒΌ” with one “flyer” that was 3 inches to the low right. Not exacting marksmanship, but the front sight post was invisible whether using one eye or two to aim. Aiming was done primarily by holding the circle of the hood under the 1 1/2” bullseye. The lock is an unmodified government issue P53 lock with a fairly heavy trigger pull and that possibly moved the group placement to the right.
The second string of five shots was fired off hand and used 60 grain charges of 3f Goex powder. Two 530 grain flat based grease-groove bullets were fired with WonderWads and three 405 grain hollow based .45-70 style grooved bullets were fired without wads. The heavy bullets struck high at 1 o’clock and 1 3/4” apart. The three lighter bullets also struck to the high right. The final group size was 2” by 1 1/4”.
Quick analysis: ignition was likely affected by the quickly modified nipple as the notch was crudely cut and not polished. The trigger pull was quite heavy, conservatively over 9 pounds as my RCBS trigger pull scale ends at 8 pounds and the indicator went past that point. The front sight post was effectively useless as it was just about invisible. The barrel was not wiped or brushed between shots.
No bullets tumbled. It seems that the Kerr rifling will digest both light and heavy bullets.
No attempt was made to develop the optimum powder charge.
The tight .451 bore is not easily loaded with .451 bullets. The shorter bullets loaded easier than the long multi-grooved bullets that I have normally used in WW (Whitworth) and .451 Volunteer rifles that tend to be a bit larger than .451. I had to force down two bullets and was reminded of the description of the Confederate sharpshooter that got a bullet stuck part way down his Kerr rifle.
I believe that the barrel will perform quite well with paper patched bullets and it will likely be a good performer with the hollow based 405 grain bullets once the various components are tuned and the sights are upgraded. I attribute the large group sizes primarily to the terrible sight picture with the “where is it?” front sight post, coupled with influences from the heavy trigger pull and the probably-impaired flame passage." [Bill put a notch in the bottom of his nipple to allow the flame to reach the flame channel to the charge. This issue is easily remedied.]
Stay tuned.
Pat in Virginia
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