powder increase Q

Just got my Dillon 550 set up for .45 ACP.  Loaded 15 rounds with 3.8 gr Bullseye and 200 gr lscw. At the range they all functioned fine.
Loaded up another 50, lots of failures to cycle. I'm sure of the charge, proofed it several times. So I'm going to increase the load a little.
Thinking of trying 4.0 gr.  Or should I load some with 3.9 and 4.0? Does .1 make a much difference?
Thanks, Kurt

I would jump 0.2 grains each step.  Might also want to try 4.2 grains.  But the key is to create an accurate load.  The gun can then be setup to run with that load by swapping out springs.

I pick load and adjust recoil spring to the load. I only adjust powder charge for accuracy at 50 yds. 25 yds they all shoot well as long as gun reliably cycles. 4.0 BE is a medium long line load: 3.8-4.2 gr BE.
I use 4.0 to break in pistols after I build them and they run fine. 
Jon

If 15 ran good why the subsequent misfires?
Not feeding?
Chamber tested them all?
Oal changed?
3.8 should work fine.

I can't claim to be a bullseye shooter, but I run 5 different 45 autos with Alliant Bullseye as low as 3,5 grs using a 185 gr LSWC & #16 Wolff variable rate springs. I currently reload 3.8 grs. I have to agree with James R. Chapman above that there is something causing the hiccups other than the powder quantity to run 16 rounds flawlessly and then have many failures out of 50 rounds. Bullseye is somewhere between a dirty to filthy powder when run at low levels. Was the gun clean with no rounds fired when running the 15 rounds & the gun dirty now? Shok-Buff? Grip change? Weigh the powder content during the 50 round re-loading? Gotta be some other factors involved? (IMHO),

Going over this, the specifics are: 15 rounds test function, offhand. YES, I had just cleaned and lubed the gun.
This AM, 20 rounds off sandbag to test group and zero, no malfunctions. Then offhand shooting at a target. That is where the failures started. so...15 rounds through a clean gun. 20, gun held solid on a bag. Malfunctions shooting offhand.  Thoughts/advice?
FWIW, these rounds do feel softer recoiling than the Wilson Combat reloads or ZERO reloads I've been shooting before reloading. I've had no issues with the Wilson rounds, and sometimes a failure to feed- as in slide doesn't go all the way forward-with the ZERO rounds.
I think the issue with the zero rounds may be OAL is a little long on some.
thanks!

Maybe you aren't holding the gun as hard off hand causing failures

Kurt

Also, this gun has a slide mounted red dot...
Kurt

kjanracing wrote:Going over this, the specifics are: 15 rounds test function, offhand. YES, I had just cleaned and lubed the gun.
This AM, 20 rounds off sandbag to test group and zero, no malfunctions. Then offhand shooting at a target. That is where the failures started. so...15 rounds through a clean gun. 20, gun held solid on a bag. Malfunctions shooting offhand.  Thoughts/advice?
FWIW, these rounds do feel softer recoiling than the Wilson Combat reloads or ZERO reloads I've been shooting before reloading. I've had no issues with the Wilson rounds, and sometimes a failure to feed- as in slide doesn't go all the way forward-with the ZERO rounds.
I think the issue with the zero rounds may be OAL is a little long on some.
thanks!

Plunk test the rounds in the barrel.  Make sure they drop in freely and drop out when you turn the barrel over.  If you have to push on they a little to get them all the way in they are to long.  Don

Sir:
Wilson's Signature load is generally 5.0 grs. of bullseye with a 200 gr. LSWC. This is generally the same load they use to test fire all of their guns prior to shipment.
Considering your gun has a Red-Dot attached, you might be on the thresh-hold of not enough powder. Also might want to look out for possible weak/limp wrist condition. Considering that they sand bagged OK, but did not off hand, I would think that limp wrist might be an issue. Also could be that the issue is not limp wrist but that the gun's movement is overcoming your grip resistance.

I'm running 3.4 @ 25 and 3.8 @ 50 zero 200 lswc

"""""Plunk test the rounds in the barrel.  Make sure they drop in freely and drop out when you turn the barrel over.""""""
Thanks, Don.  Actually I did do that, I'm good there. My COL is a couple CHs shorter than the Wilsons.
Gary, I'm not a limp wrist kinda guy...

kjanracing wrote:"""""Plunk test the rounds in the barrel.  Make sure they drop in freely and drop out when you turn the barrel over.""""""
Thanks, Don.  Actually I did do that, I'm good there. My COL is a couple CHs shorter than the Wilsons.
Gary, I'm not a limp wrist kinda guy...

OK, let me re-phrase that statement. What I meant to say is that shooting the gun off-hand may not present the necessary resistance to duplicate the sand bag function results.
Please consider the revised statement and accept my apologies for the previous phraseology.

kjanracing wrote:"""""Plunk test the rounds in the barrel.  Make sure they drop in freely and drop out when you turn the barrel over.""""""
Thanks, Don.  Actually I did do that, I'm good there. My COL is a couple CHs shorter than the Wilsons.
Gary, I'm not a limp wrist kinda guy...

Limp Wrist is a common shooting term and in this context means no more then not locking up the wrist so the slide does not cycle.  I have seen many shooters at the indoor range take a new gun they bought to the range master and complain that something is wrong with it.  I think I have even relaxed to much while shooting for fun and had it happen.  

Now if you have a optic riding that slide it can effect it but you said bench rest it was ok.  Don