Trailblazer
10-01-2008, 01:16 PM
I wanted to go deer hunting with my 1873 Winchester this year. I live and hunt in the lead free buzzard zone so I can't use cast. I bought a box of Barnes 44 XPB's to try. High priced bullet - about a buck a pop! Don't waste 'em! Barnes makes two versions of the 44-200 XPB. One for 44 mags that expands down to 1050 FPS and one for 44 Special that expands down to 850 FPS. I bought the 44 Special version but the cannelure is in the wrong place. I figured the simplest method to use to keep the bullet from being driven into the case in the magazine is to use a powder that fills the case and supports the bullet. I settled on IMR 4227.
I loaded three rounds last week to get velocities. One each at 15 grains, 16 grains and 17 grains. The 15 grain load did not read on my Chrony. The 16 grains went 897 FPS and 17 grains went 1030 FPS. This week I loaded five at 18 grains. They averaged 1130 FPS which is about what I wanted. All were shot at 50 yards.
The trouble is they show definite signs of tipping. The holes in the target are round but there is a dirty smeared tail on one side. The slower loads I shot last week showed a slight "tail" on one side but I didn't think anything of it at the time. The faster loads have much larger "tails". I don't get it. It looks like the faster loads are tipping more than the slower loads. There must be something else at work here.
The rifling is shallow and has a fine roughness - almost like worn 40 grit sandpaper. It shoots cast very well in spite of that. Twist is 1/36" .Groove diameter is .430" The XPB bullets are .428" to .429" and are somewhat longer than the cast bullets. I didn't see any copper fouling at the muzzle last week. I did not clean it because it always throws the first shot out of the group. That didn't work because it threw the first shot out even with the dirty bore this week. It does show copper on the tops of the lands this week. Accuracy is acceptable for a short range rifle.
The question is why would an increase in velocity cause the bullets to tip more?
I loaded three rounds last week to get velocities. One each at 15 grains, 16 grains and 17 grains. The 15 grain load did not read on my Chrony. The 16 grains went 897 FPS and 17 grains went 1030 FPS. This week I loaded five at 18 grains. They averaged 1130 FPS which is about what I wanted. All were shot at 50 yards.
The trouble is they show definite signs of tipping. The holes in the target are round but there is a dirty smeared tail on one side. The slower loads I shot last week showed a slight "tail" on one side but I didn't think anything of it at the time. The faster loads have much larger "tails". I don't get it. It looks like the faster loads are tipping more than the slower loads. There must be something else at work here.
The rifling is shallow and has a fine roughness - almost like worn 40 grit sandpaper. It shoots cast very well in spite of that. Twist is 1/36" .Groove diameter is .430" The XPB bullets are .428" to .429" and are somewhat longer than the cast bullets. I didn't see any copper fouling at the muzzle last week. I did not clean it because it always throws the first shot out of the group. That didn't work because it threw the first shot out even with the dirty bore this week. It does show copper on the tops of the lands this week. Accuracy is acceptable for a short range rifle.
The question is why would an increase in velocity cause the bullets to tip more?