Fighting with my .41.......

[kevmc]

I'm working on a load for my .41, SW 657-3 PC Magnum Hunter.
Casting with one of Miha's--MP 41-258 solid, 50/50 #2/PB, sized .4105 and BAC lube.
Bore slugs at .409, Throats at .410
Using 2400 and Fed 150 primers, 16 grs giving about 1175 fps.
Groups are 4-5" at 50 yds, iron and Aimpoint (5 min dot).

Velocity varies too much to suit me, most around 1175 and then one at ~1070......
Once fired Starline cases.
Primer pockets are cleaned, primers fully seated, charges are thrown with RCBS Uniflow and consistent.
The action was done by a good 'smith I trust, but I did try swapping the mainspring for new, same results....
Hammer does not appear to be dragging on frame.
I've upped and downed the charge from 14.8 to 16.9, same results.
Inconsistent ignition??

Next to try, I've mounted a 2.5X scope to help sighting, but I'd like to see more consistent ballistics......
Mag Primers??
2400 should be a very good powder for the .41........H110??
Other Ideas????

[Airman Basic]

How's it shoot with factory rounds?

[kevmc]

Haven't shot a factory loaded round in many years............with this gun, never.

[HeavyMetal]

Switch to WW 296 and use standard primers, you are already using a single HS for brass my next question is have you trimmed to a specific length as a crimp control?

This is usually the missed step in accurate pistol loads.

Next try weighing your castings and try to keep them lot specific with about 1 grain plus or minus your average weight as acceptable.

[williamwaco]

My favorite powder for your need is Herco.
You will give up 50 to 75 fps but you will gain in accuracy.

[kevmc]

I need to check case length......
No ww296 or Herco on hand....
I'll weigh bullets and load with H110 and send 'em down range!!!!

[iron mule]

check the cylinder barrel gap and alignment
also check the diameter of the cylinder at front end and check the throat of the barrel check both diameter and angle
this may be the source of you inconsistency
mule

[runfiverun]

after all that.
pay attention to the press handle your neck tension is varying from case to case giving you the drop off.
don't think so?
try another round of 18 loads, pull the inconsistent velocity ones, mark them, and then shoot them again.

[45 2.1]

Once fired Starline cases. Other Ideas????

Most of the time new cases in magnum calibers need to be somewhat harder in the neck (like several firings) before they produce good accuracy. I would suggest taking about a dozen cases and running them in and out of the sizer 4 or so times each and try them to see if that helps.

[cbrick]

Hhmmm . . . Most consistent/accurate loads I've tested in magnum revolvers were with virgin brass.

Most accurate 41 Mag load I've yet developed was with Viht N-110, 19.5 gr & virgin brass. An honest 3" group at 150 meters from the bench with a Burris 12X. Lead Heads 240 gr TCGC @ 1520 fps and an extreme spread of 22 using 414 Super Mag brass (Starline) trimmed to fit the FA chambers, standard primer.

If you can't get viht powder use the 296/H-110 keeping in mind that these ball powders only work their best at or near full book loads. Couldn't hit a barn if you were standing inside it with a reduced charge of H-110 & many say it's a dangerous thing to reduce it.

The boolits came from LeadHeads at 18 BHN.

Rick

[kevmc]

I've got some loaded now to try in the morning.....
Clean starline cases, trimmed to length, primer pockets uniformed, flashholes deburred, wt. sorted to 1gr.
Fed 150's carefully seated under 16 grs (weighed) of 2400.
Bullets within .5grs.

I plan to shoot all from the same chamber, over an Oehler 35P chrono (with proof chl).
Think I'll get some good info from this......
More tomorrow after I've shot 'em!!

[44man]

I bet the boolits are too soft. Try oven hardening some or reduce the pure lead. Try straight water cooled WW boolits.
You are not maintaining even neck tension case to case, your dies might not have a good expander. But with soft lead, you can size when seating and that is no good.
Check fired brass to see if any part of the crimp is not unfolded all the way.

[kevmc]

50/50 #2/PB (94-3-3) bhn should be about 11-12, (EK's 16:1 about the same), bullets I've loaded and pulled did not appear to be sized by the case/crimp.

neck tension or inconsistent ignition.........my guess's....see what I get from post 11 exp.!!

[GLynn41]

I had the a similar problem-- and by skipping the belling expanding or make the xpander smaller --it went away completely for me-- I use a number of Gary Reeders .41 wildcats just a champher or smaller expanders - went from 100+ fps between rounds to often less than 10 -- your sizer die may not be small enough -I want a small bulge to show the case has a good grip ( which you can not do with Gary's small bootle neck rounds) but is easily seen in a straight wall round--I own nothing but .41s- try the champher 1st -

[kevmc]

Inconsistent neck tension thoughts..........
We lube the bullets and load into the case......
Are we not then putting lube on case walls above lube groove......????
Using BAC.....works great in my .44 (as does the same lot of 2400/fed 150's, BAC, and bullets of same alloy, but with
GC 429640HP...)

[kevmc]

Results from post #11 exp.

only 7 rnds, more to follow (gotta cast more bullets!!!!!)
XS = 39
Mean = 1102
SD = 14
interesting drop in mean velocity...........???

[Mal Paso]

2400 is excellent powder but burns inconsistently with lower charges. My regular target load in 44 Mag with a 260g boolits is 19g of 2400 and runs about 1260 fps from a 6" 629. 20-21g depending on manufacturing lot variation is my top end with that boolit in a S&W 629. A bit more powder should tighten up the velocity.

H110 is slower with an even shorter useful range and you need a long barrel or a heavy boolit to take full advantage.

[runfiverun]

Inconsistent neck tension thoughts..........
We lube the bullets and load into the case......
Are we not then putting lube on case walls above lube groove......????
Using BAC.....works great in my .44 (as does the same lot of 2400/fed 150's, BAC, and bullets of same alloy, but with
GC 429640HP...)

this really only has a lot of effect if the lube is too slippery.
it doesn't effect the neck tension just the release, and whether the wet lube is blown ahead of the boolit or if it makes the trip attatched.
neck tension is more like grip force.
think about grabbing a bar of beeswax versus a bar of wet soap that's the difference lube friction/viscosity makes.
if it is consistent from shot to shot the release will be consistent, if the grip force vary's from shot to shot the release will come at different points along the pressure window.

[kevmc]

2400 is excellent powder but burns inconsistently with lower charges. My regular target load in 44 Mag with a 260g boolits is 19g of 2400 and runs about 1260 fps from a 6" 629. 20-21g depending on manufacturing lot variation is my top end with that boolit in a S&W 629. A bit more powder should tighten up the velocity.

H110 is slower with an even shorter useful range and you need a long barrel or a heavy boolit to take full advantage.

I'll up my charge and try it......

Remember I'm loading a 41 Mag. /220 gr

[41mag]

If you have any AA- 5 or 7, they have been working well for me and my hunting partner. He shoots the S&W and I'm running a RH.

[**oneshot**]

I shoot a 41mag. 210gr Saeco SWC with BAC/Cred 3-1 bended lube. I have used 2400 and had good results in the charge weights your using with Federal Large Pistol primers. Best results with 2400 came near the top of the Lyman cast bullet #4 load data. The closer to the top end I got the lower the velocity spread became. I also found that crimping just until the case mouth wouldn't grab my fingernail worked the best with my boolits. 75%coww 25%pb + tin Air cooled, Sized to a really snug fit on the cylinder. I can push them through with a good amount of finger pressure.

[kevmc]

17.4/2400 gave a nice 2.5" group, but still almost 100 fps extreme spread, sd = 43.......
18.2/2400 started showing vertical groups and 100 fps XS sd =47

19.5 / H110 looks good. 1209 fps, XS = 43 SD = 12, (12 rnds.), and a 2.5" group..
I'll work with this some....