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Thanks Curly, I feel quite lucky to have them.

I'm hoping to get to the range again today or tomorrow to try out 12 rounds in the 500/450 and see how that rifle groups with a proper sample size of rounds. I also plan to shoot the 450 Lancaster with a higher charge of 4198 based on a load from Wright's 4th edition. My current load of 45gr 4198 and a 300gr JHP are printing high and velocity is under historical speed for this round by 100-125fps. I'm hoping the higher charge brings that down without introducing crossing impacts.

Chris

Chris,

How was your new grouping and what load did you use?

BTW, although your earlier 50 yd group was very high, it was excellent, very tight with both barrels regulated.

It was not a great outing, other than letting a dad and his two sons shoot a double rifle for the first time.

I ran into a couple of problems. First, I forgot to print off different targets for 50 yards vs the usual 30 I do load development at. The targets I had with me had a very small bulls eye, so other than testing for elevation, it was hard to do anything about horizontal dispersion. I had blue masking tape with me and should have made my own on the spot. Next biggest issue was primer failures. I had a squib load and a hang fire. I'm using CCI BR-2 large rifle primers. I don't know if I got case lube on them or what, but I definitely had inconsistent ignition issues I didn't have last time.

Do you use an over-powder wad card before your foam filler? I am not. The cartridge cases I use store the rounds with the bullets facing down. I'm wondering if the powder is migrating into the kapok filler.

The last challenge is that my range is the primary outdoor range for a number of local police departments and 3 different towns were using it when I got there, so I had to use the main rifle range, and not the smaller berms where you're shooting by yourself.

Any advice on primers? Do you use Federal 215s or magnum primers?

Do you think that ignition issues are likely why my Garmin was recording some pretty inconsistent velocities (I weighed each charge and all the cases had been cleaned).

Chris,

Too bad that things didn't work out.

I have had primer issues also. I use Winchester LR primers and have had a few 360EX loads not fire, even though there is strong indentation on the primers. I attribute some of my failure to fire as perhaps the primer somehow got contaminated.

I have not seen much difference in performance using different primers. I use Winchester because that is what I could find. Previously, I used Federal primers.

In a different type weapon, I had the primer ignite but the powder failing to ignite. The bullet was driven into the barrel by the primer. Now that was my Ruger SR 454 and the load was 30 gr H110. I I am glad (lucky) I realized the problem before firing another round. I now use magnum primers with that gun.

However, with low pressure loads with the powder against the primer (held in place by the filler), I believe the issue is a primer issue. It sounds to me like there is inconsistent igniting the powder, giving inconsistent velocities. While I would think that regular primers would ignite your powder load, you might try magnum primers, just to see if there is a difference.

Now the main spring on some older guns will not fire magnum primers and one rifle I shot would only fire LP primers.

I don't use over-powder wads. I don't thing that the amount of powder that migrates into the filler is significant (if any powder does actually migrate)

I use a packing foam rod filler that is cut so that the base pushes against the powder and the top is at the case mouth. Seating the bullet compresses the foam filler.

Now, all that being said, the last time I was at the range, I got very inconsistent velocities with my Sherwood but fairly nice group. I was using 12.5 gr of 4198 which fills the case very well. However, with a long, skinny case and long stick powder, there could be an ignition issue.

Thanks Roy.

I don't know if I contaminated the primers as I was using the primer slide built into my Redding press, and feeding that one primer at a time, which is what I always do when reloading for express rifles, since the round count is manageable. But I may have gotten sizing wax/lube on them? Don't know. I have magnum primers here and have used those before. Will switch to those and keep the BR-2s for modern (e.g., smaller) cases.

Chris,

Ross Seyfried had a similar problem of his double rifle regulating but 5" above the aiming point. He wrote about it and his loading solution in DGJ Vol 7, Issue 3 (Autumn 1996), page 53.

If using a different load didn't work, I would be inclined to replace the front sight with a higher sight as the regulation is great. Of course, I would keep the original front sight to pass on to the next custodian.

Roy, I'm heading out today or tomorrow to try the 500/450 Lancaster with a different and higher charge to see if this brings POI down without expanding the excellent groups I saw with 45gr 4198. I'm also loading up LFN bullets for the 450 3.25" Lancaster that did so well with jacketed bullets already. I plan to bring both to Rick's shoot, and like use one for the DR stage.

I am having brain cramps this morning as I make this request. Will someone explain to me how a rebounding lock works versus a non rebounding lock. And please, save us all the time by not saying that " one rebounds and the other does not"!!! Not that there would be any wisecracks from this group!!! Thanks in advance. If it is a ridiculously simple answer that should not take up board space feel free to PM me. Again, thanks in advance.

Here's my non-technical answer:

Originally, flintlocks and percussion guns were non-rebounding...they usually had a half cock notch and a full cock notch. When you pulled to full cock and pulled the trigger, the sear would move out of the full cock notch and the hammer or cock would fly fully forward and hit the frizzen or percussion cap. And stay there. It didn't move till you pulled it back to half cock to load the next round.

With cartridge guns came along, the locks stayed the same...they had a half-cock feature, and that's also where stalking safeties would slide into to keep the hammers from moving. Still not rebounding...the firing pin(s) stayed fully forward until you pulled the hammer back. So in my Lancaster with non-rebounding locks, you can't open the action until you have pulled the hammers back to half cock as the pins are forward of the breech face and hang the barrels up from opening.

Rebounding locks don't have a half cock notch per se, at least in my understanding. When uncocked and at rest, they are not pushing the firing pins all the way forward into the primers. That only happens when you pull them to full cock and pull the trigger...they fly past their neutral space enough to detonate the primers and then pull back, or rebound, so the firing pins are pulled away from the primers and the action can be opened with out touching the hammers.

Someone may be along to correct this, but this is my understanding from messing around with my guns.

Chris,
Your explanation is correct. The neutral position for the hammer is slightly off the firing pins. For that reason, a half cock and hammer safeties were not needed.
When the hammer fell, the momentum carried it past its neutral position to strike the firing pins. The hammer spring would bring the hammer back to its neutral position.
Now some rifles were made with rebounding hammers and half cocks; An Austrian double rifle I had was made with both rebounding hammers and half cocks.