40 cal . Accuracy

[chief99]

After many conservations on a load for a 40 ca. , 140 gr. lead bullet , have finally settled on a reliable and accurate load. 4.4 grs. of Bullseye . Cycles well and very accurate at 15 to 21 yards. Played with the load several times before I settled on this. Question ? Also loading 40 cal. , 165 gr. Berrys copper plated . Currently using low to mid range jacketed data . Loading 5.2 grs. of Bullseye . Not as accurate as the lead . Should I experiment with different charges on the 165 gr. copper also . Thanks.

 

[LiveLife]

Should I experiment with different charges on the 165 gr.

I would adjust the OAL/COL first then conduct a powder work up to determine the most accurate load. If your barrel will feed and chamber longer OAL, try loading the bullet longer than SAAMI max of 1.135" to reduce high pressure gas leakage.

My Glock and Lone Wolf barrels will accommodate 1.149" max OAL with typical jacketed/plated/lead TCFP nose profiles and feed/chamber 1.145" but I used working OAL of 1.143" to compensate for mixed range brass case length variation - http://www.thehighroad.org/showthread.php?p=9362819#post9362819

1KPerDay had accuracy issues with his Berry's plated load and loading longer than SAAMI max did the trick to improve accuracy - http://www.thehighroad.org/showthread.php?p=9416978#post9416978

 

[rsrocket1]

4.4g BE under a 140g bullet is a pretty low recoiling load (about the same as 9mm). 5.2g under a 165g bullet is quite a bit stiffer and more in line with a typical 40 cal service load. Are you sure your single shot accuracy is worse or is it "full magazine worse"? I'll bet your 140g bullets are going around 950 fps while your 165 bullets are going 100 fps faster. That's about 1/3 more recoil. To get an equivalent recoil from those heavier bullets you'll need to down load them to about 3.5g BE. Since that is below "starting" charge "by the book", whether you want to do this is up to you and you should work down. The recoil will be the same, so the cycling should also work just as well.

Shooting with a polymer frame gun will amplify the difference because the lighter weight of the gun will recoil more than with a heavier gun such as a 1911 or a big frame 357 size revolver.

The above isn't proving much other than your accuracy issues may be related more to recoil than to load. Unless you are shooting from a ransom rest.

Good luck.

 

[GLOOB]

Not as accurate as the lead.

Is this by shooting groups on paper and measuring with calipers? Or is it a grossly observable problem to a good shooter after a number of rounds?

If it's a gross problem, the first thing I always suspect is damaged bullets. I would pull some and check the base. Berry's plated bullets are MUCH softer than cast bullets. And the 165 will probably seat a little deeper than the 140's, which increases the damage that the base will take, IF your sizing die is tight.

When I loaded Berry's bullets, I made custom seating plugs, else the nose was damaged (largely cosmetic, but it did mess with OAL, a little). And for 40SW and 9mm, I need to use custom oversize expanders for plated/coated/cast, because my sizing dies in those calibers are tight.

Heck, if I load a cast bullet into a cleaned and degreased case in 40SW or 10mm, I can't get it back out with a kinetic bullet puller. If you have a tight sizing die in this caliber, your bullets are in for some trouble. The bullets seat so deep in the case; I think this may be the reason some guys get better accuracy with a longer OAL.I erroneously thought I couldn't shoot my G27 near as good as my G19 for years, because of this issue. First time I used my custom expander and a fairly mild load, I shot the lights out; it was like shooting a different gun.

Another thing you may find helpful is to sort cases. Try using only R-P, Speer, Blazer, FC, and Winchester for your non-jacketed bullets. Avoid any other headstamps, and especially S&B, Fiocci, and PMC cases, in particular. One way to accurately detect the thicker cases after-the-fact is to put calipers over the case mouth on your loaded rounds, just below the crimp.

 

[1KPerDay]

Best I've personally found for the 165 plateds is 5.0 grains of WST at 1.125"ish.

Works well in my Glocks.

I had a hell of a time finding an acceptably accurate load for 180 berry's plated tried about 15 powders... you can search my threads if you're interested. Eventually messing with the COAL seemed to be the key. When in doubt, try loading them longer (still pass the plunk test).

 

[DeltaVictor4]

My .40 S&W data

Platform-Springfield XDm 4.5"

Try upping the bullet weight to 165 or 180gr, especially for longer shots. I shoot both hard cast and jacketed in 180gr with W231 powder and have good accuracy out to 20yds. COAL is also important. Also, make sure the topside of the chamber is scraped out on occasion (at least with the XDm) to make sue consistent round seating. This is what I found out to work for me.