N120 and harvester light “BLUES”

[ElDiablo]

Did they fit your bore tight like mine did? I had to really lean on the ramrod with both hands!

No, not unusually tight in my McGowen .45. Maybe I need to anneal and/or go with a heavier BH209 charge.

 

[LHR]

Have you tried a wool wad over powder n under the sabots ? Was the barrel hot from firing ? Just a tip on sabots do not let them get in the Sun & then load them. I use very mild loads of VV110 n 4759 from my .45 using .40 bullets

Tried wool as well as a veggie wad to no real benefit.

 

[capttoddjones]

Just back your load off. Too much pressure.

 

[The long rider]

Reloader #7 is the most sabot friendly powder there is I set a Remington 700 ML with a McGowen .45 bbl. some years back using H-4198 and 200 gr. Hornady SST bullets. He lost a couple of deer so I switched the gun to the Pittman .40 cal 225 gr. and the Harvester lt. blue sabot. We also changed to Reloader #7 powder using 72 grains. With this combo we get 2675 FPS. and deadly accurate.
The bullet that you are using has a long bearing surface which could be causing more pressure and blowing the sabot. I have also seen sabots that were 3 or 4 years old and exposed to excessive heat fail when a fresh box would not. That Harvester sabot will blow with any bullet/powder combo when it gets to about 37,000 psi.
I believe it is the longer bearing surface causing your issue. I built a .40 cal smokeless gun last year and used the Pittman 228 gr. bullet @ 3100 FPS. with VV N530 powder. That bullet was sub moa at that speed ,but I would not get a pass through because the bullet was being driven too fast. I bought a 50 pack of the Fury 240 gr and sized them for my bore I dropped my charge 3gr.s to compensate for the heavier bullet.
With the reduced load and heavier bullet that bullet still broke 3000 FPS. It also loosened up my primer pockets on my Hankins primer modules. I would up dropping another 3 gr.s of powder to get the pressure down enough to not blow my primer pockets. I believe it was because of the longer bearing surface of that Fury bullet and not just the extra 12 gr.s of weight.

 

[jsteurrys]

How is Reloader #7 at around 60 grains?

 

[The long rider]

IMHO It would depend on what weight bullet you chose to use. If you were using a 200, 225 or 250 gr .40 cal bullet/sabot combo in a .458 smokeless gun, I would say it should equal a 100 gr. Blackhorn load. I have never shot that small of a charge of Reloader #7

 

[ny hunter]

What temps you shooting in also makes a difference.I use
H4198 51 grs with tan sabot plus a xtp 180 .Light blue too loose for my barrel CVA conversion

 

[MeatMachine]

I almost mentioned bh209 but I was thinking use a smokeless powder with a similar burn rate. Here are two of the same Lehigh .400 caliber muzzleloader all copper bullets. The one on the left is not annealed and tumbles and hits a target sideways at fifty yards in my rifle and the one on the right is annealed and stacks them at 100 yards.

I should have mentioned that I was using imr 4759 powder in a harvester smooth blue with this 195gr copper lehigh. I tried one other un annealed shot with imr 4320 for chits and grins and that seemed to straighten out its flight path but I like 4759 for its ignition and easy on the sabot qualities. Annealing the bullets solved the problem.

 

[Mnt monkey]

I've got about 30 lb of that old powder stowed away that's good information I appreciate it