[T/C nimrod]

Anyone who is/has shot this caliber ever experiment with seating depth? This project I started a few months back is turning into a real adventure in load development; 5 shots making one rough hole at 50 yards, and no better than 1.79" at 100 yards AAAGGHH!! I was curious if oal(col) would make any difference, or if crimp pressure would have the same effect.?

 

[Javelina]

41 Accuracy

Hello,

I shot a .41 Mag 14" T/C factory barrel for years. I found that other than powder, primers and cases in good condition, the following were worth the attention:

1) Ensure that case lengths are all identical - trim them to the same length with each firing.
2) If you're using a carbide sizer, try only sizing the first .400" of an inch of the case - leave the rest of the case unsized, as long as it will still fit into your chamber. Make sure all the cases are sized in exactly the same manner.
3) I had my best luck with Sierra 170's and Sierra 210's in that order
4) Experiment with seating depths - my best accuracy was with the bullets seated pretty far out. I still tried to keep enough bullet in the case so they wouldn't fall out.
5) Uniform your primer pockets - I'm lazy and got the Sinclair drill attachment for my primer pocket uniformers - what a wonderful time (and wrist) saver!
6) Use a scope of sufficient power to see your target correctly at 100 yards, it does make a big difference.
7) Index your cases. Make a small mark with a file on the rim and place the mark in the same place for all reloading operations. Place the bullets in the chamber with their marks all pointing to the same spot (i.e., point all the marks at the center of the extractor). Indexing cases has proved to be more effective for me than any other reloading tip. Do it religously and it will make you a happy camper!
8) Use Fastex and coat your bullets - what an improvement!
9) You can always have the barrel rebored to a .41 GNR #2 by Gary Reeder Custom Guns. I now own a 13" SS Reeder .41 GNR #2 (.445 SuperMag case necked down to .41 caliber) with a muzzle brake. . .believe me, YOU WANT ONE! Accurate, flexible and hydrostatic shock you won't believe with .41 caliber 170's flying out at over 2,600 fps - what a rush!

I hope this information is of help to you. Please don't hesitate to contact me with questions/comments.

Javelina

 

[T/C nimrod]

Javelina - Thanks for the great info, But it's not that easy:1)Cases are all new lot, same headstamp, exact trim length (to the .000")
2)I'll try this one - moving the die up to partially size
3)I will be loading all bullet weights and manufacturers' - right now it's Sierra 210 JHC (all bullets weigh 209.7 to 209.9 grns.)
4)Seating depths is where I am now - I have the bullet just out of the lands (1.612") in my barrel w/ a heavy crimp. I tried the seating depth first w/o crimping and found inconsistent ignition w/o the crimp. The next load I work up I think I'll use 20.1 grns./H110 and vary the oal(col) as the only difference between groups (of 5).
5)Primer pockets were done w/ trim length
6)I have a Burris 10x on the barrel for load development - no problems w/ target accusition @ 100 yards
7)This is a good point, but up for discussion. I feel that minimal runout and consistent seating practices make indexing unnecessary. I'm a hunter, and the last thing I want to worry about is which way I dropped my second case in the barrel (hopefully this will never happen, but I don't need to worry about an index mark)I also weigh my cases; so I feel that I can pick any random case from this lot of 50 and it will be e-x-a-c-t-l-y the same as any other random pick.
8) Fastex? I must be living under a rock, never heard of it.
9) Rechamber? and admit defeat? not a chance!! I started this project with a goal - I'm not going to stop until that goal is achieved.

You gave me a few avenues to try - looks like rain the end of the week, maybe I will get a chance to work some more rounds up.

What kind of accuracy were you getting at 100 yards? Just looking for comparison reasons. So far I would say I'm averaging 2" groups/5 shots at 100. The barrel averages just a smidge over 1/2"/5 shots at 50 yards. I guess that's my hang-up.....great at 50 should be great at 100. Thanks again!

 

[Bullseye]

I am shooting a 10" barrel and have about the same accuracy as you at 50 yards. Never tried it at 100, but you have my curiosity up. One thing I have noticed is the barrel seems fairly finicky. I am shooting 296, but varying the load by a half grain either way makes a definite difference in group size. My barrel would not group good at all with IMR 4227 but I am going to go back and try it again.

One comment you made is about lengthening the COL. If you are shooting 110 or 296, you need to have a good crimp to get good ignition. With that long of a COL, are you crimping into a crimp groove. If you are crimping in an area without a groove, I think that would make the accuracy worse without a doubt.

Good luck and maybe I will try the 100 yard range Friday.

 

[T/C nimrod]

yep, crimp groove (cannelure) is out of the shell about 1/8". I'm crimping into the jacket. A discussion w/ Sierra about this procedure yielded the comment that the cannelure is on the bullets for industry standards. I took that with the same outlook on listed oal(col) of cartridges "each application may vary". Keep me posted how yours makes out at 100 yards.

 

[Javelina]

.41 Mag Accuracy

T/C Nimrod,

My accuracy with a 14" factory .41 Mag barrel finally got down to about 1 1/8" to 1 1/4" at 100 yards (although, I have to say that my .41 GNR #2 is currently shooting about half that - I wouldn't complete discount a rechamber if I were you). I believe the hollow point pistol bullets I shoot are more prone to be affected by the physics of flight much more quickly than pointed designs (i.e., accuracy at 100 yards is much more adversely affected than a pointed design even though accuracy was good/great at 50 yards). Hollow point pistol bullets were never really designed for the speeds and distances we use them at these days.

Nevertheless and the hollow point pistol bullet design notwithstanding, I had good luck with the Sierra 170's and 210's. My chronographed speeds for the 170's were in the 1,950 fps range and the 210's got about 1,825 fps. I used H110/W296 (they are the same powder according to Phil Hodgdon) with large magnum pistol primers and did not crimp. I'm sure my carbide sizing die had something to do with that as it sized quite small, similar to what a small base die might do for a bottle-necked cartridge case.

Here's a tip on bullet seating, it takes a little extra time, but you can get very fast at it and it helps me a lot whether I am seating straight wall or bottle-necked cartridge bullets (an index mark helps here, but is not mandatory). When seating your bullets to the selected depth, only seat about a third of the bullet's depth and stop - rotate the case about one third of its circumference - seat another third of the selected bullet depth - again rotate the case about one third of its circumference - seat the last third of the bullet's depth. I have had excellent luck with reducing runout due to seating errors this way and you can do it very quickly with a little practice. You will quickly develop a feel for it.

If you are throwing powder charges, you may try checking the weight more often or weighing each charge individually if it comes to that (powder weights have been known to vary for a variety of reasons when they come out of powder measures, so a check with a good scale can't hurt). You may also want to try some Hodgdon Lil Gun powder, I've had some good preliminary results with it in straight-walled cases and velocities are very good.

Assuming that the mechanical part of the reloading process is in good order and you have deburred your flash holes and checked for uniform diameters of those flash holes, if powder charges are correct as measured, then I believe your only realistic options are bullet seating depth and bullet selection. What type of bullet is being used and how far off the lands it is seated will be the determining factor in how well you can get your barrel to shoot. You may want to have an experienced and knowledgable gunsmith check the alignment of your chamber and throat to the bore itself. Again, not to harp too much on case indexing, but accuracy problems stemming from a bad chamber/throat alignment to the bore can generally be greating improved by indexing your cases and using a uniform method to place the case into the chamber - really, you will be amazed at how much accuracy can improve by doing this.

Good luck with your efforts - let us know how your project goes!

Javelina