I've been getting excellent regulation and accuracy out of my Merkel 470NE using GS custom 500grn running at just below 2000fps
Load is 95grn AR2209(H4350) Fed215, Norma brass

I'm struggling to duplicate the results using Woodleighs' 500Grn RNSP.
My Woodleigh loads are running at slightly higher speeds with the same powder charge and crossing at 25yrds and further out.

So the obvious thing to do is drop the charge to reduce speed, but I'm hesitant to drop further as all the load info I can find is 10+grn hotter and 100+fps faster than my current load.

Maybe I just have a slow gun/chrony?

Any suggestions welcome

Regards
H

I don't load for the 470 and I'm not familiar with safe loads or proper powders, but when I was messing around with my 458wm double rifle, which has a list of poweders the length of your arm acceptable for the cartridge if not the rifle's regulation, I found that there are at least two if not a theoretical serries of the X's described by Wright in his book.

None of the powders I tried would describe the full two or more X's without going below or above recomended loads, but I could definitely plot the two X's, with loads spreading and then coming together in regulation and then spreading again.

Some powders showed good tight but not crossing groups well below the velocity I was seeking.

Perhaps adding more velicity will be the ticket, or maybe a different posedr would be a better choice.

JPK

quote:

Originally posted by HendrikNZ:
I've been getting excellent regulation and accuracy out of my Merkel 470NE using GS custom 500grn running at just below 2000fps
Load is 95grn AR2209(H4350) Fed215, Norma brass

I'm struggling to duplicate the results using Woodleighs' 500Grn RNSP.
My Woodleigh loads are running at slightly higher speeds with the same powder charge and crossing at 25yrds and further out.

So the obvious thing to do is drop the charge to reduce speed, but I'm hesitant to drop further as all the load info I can find is 10+grn hotter and 100+fps faster than my current load.

Maybe I just have a slow gun/chrony?

Any suggestions welcome

Regards
H

H

I have a Merkel 470 and a Chapuis 470. The Chapuis has very tight chambers and will regulate with 86 grs of rl15 and crossing at 86.5, the Merkel is still shooting side by side at 92 grs. Same lot of powder same batch of bullets. You may have a larger bore dia , if your bore slugs at 475 it will not build as much pressure as one that slugs .474. There are a lot of reason for it to vary from the norm.
If its crossing back off on the powder. You could also go up and see if they will spread apart use your chrno to make sure you are not shooting faster than the factory regulation load. Try some rl15 with foam or Koch wads. make sure the charge is compressed. 86 grs is about right. Or some rl 19 with out fillers. Do you have a copy of "Shooting the British double"

What rifle are you shooting.

I don't have a 470 but agree with the post about trying different powders. in my 500/416, my load for the GS Customs uses a different powder than the load for Woodleigh or Hornady softs.
Peter.

Thanks for the input so far. I've loaded a batch with 2209 and 2213sc, will test tomorrow if the weather permits.

I've also got some Hornady DGX - so if anyone has pointers for loading those I'd appreciate it.

I've got Wright's 3rd edition, Nick Harvey's 7th . ADI 4th Ed, Hodgdon's data and Pierre vd Walt's article from the BigBore Journal No 23, Sept 07 as well as info from here and various other sources.

Regards
H

quote:

What rifle are you shooting.

Merkel 140A 470NE sxs double.
2002 model non ejector.

My Merkel liked h 4350 and rl 19 , it also liked NF cup points. It also likes H 4831 (but that powder kicked much harder than the others).
It shot all of the above in little tight clusters. It was just so-so with rl 15 and woodleighs. It was still good enough to hunt anything you wanted with it.I had a rl19 load with cup points or cast lead that would shoot about 2"- 2.5" at 75 yards on a good day.

JD

It may be that your Merkel was regulated with a slow batch of factory loads. Check to see what it was regulated with. If you want over 2,100 fps, you may have to have it re-regulated. J.J. at Champlins can do it for you.

465H&H

465, a little difficult perhaps as this guy is in NZ!
Peter.

NZ has a very capable person who can build and re regulate Double Rifle's.

I think he was trained at Purdey's or Holland's
and has built barrels from scratch.

Does nice work.

I don't think we are at the re-regulate stage just yet gentleman.

Chrony died on me at the range so no shooting today. I'm usually happy to burn powder to test stuff but I know without decent data I'll just be wasting my time. So I'll head out again in a few days and see how the test loads perform.

If anyone has details of the "very capable person" I'd be grateful.

Cheers
H

Results today at 25yrds



Groups are looking good and I think I'll stick with 92grn of 2209/H4350 at around 1900fps.

Don't take this wrong. You are not shooting well enough to decide this based on what I am seeing. You are getting a mixed group, you don't know what you have,except its not tight enough per your standards. You could hunt with either load. Work on your shooting form and move back to 50 yards. My rifle like 98 grs of h 4350 and 500 gr bullets.

Please correct me if I am wrong but wouldn't a larger load of a slower powder intended to reach the same velocity not generate a sufficiently higher recoil (due to it's larger accellerated total mass) to make the gentleman's rifle cross farther out?

I believe for your rifle if your ever going to get a 500 grain bullet around 2100 your going to have to use a slower powder like IMR 4831 or your going to see R L cross-overs. Plinking loads for 470 and 1900fps are great but hunting loads I would want to see 2050-2150fos,

Thanks for the feedback guys.
Back to the drawing board and moving out to 50yrds

Cheers
H

Try 96gr of h4350 then 98gr quit when you near 2150. It may shoot apart with these loads. Some doubles will shoot apart then cross and shoot apart again with different loads of the same powder. Check with your chrno to make sure you don't start pushing to hard. I also had good luck with rl19.I like 2 targets side by side one for the right barrel and one for the left.Call your shots and mark them on a scratch pad. With two targets it easier to see how each barrel is grouping and if loads are crossing the point of aim. Doubles are hard to shoot for accuracy, slower lock time, hard kicking loads, a twisting during recoil,and heavier triggers than bolt guns. How you react to the recoil each time is important with a double rifle.
You got to try to hold them the same each time.
A standing rest or good sticks are better than using a bench rest type set up even when you hold the forearm and rest your hand on the bench rest it self.


JD

quote:

Originally posted by DUK:
Please correct me if I am wrong but wouldn't a larger load of a slower powder intended to reach the same velocity not generate a sufficiently higher recoil (due to it's larger accellerated total mass) to make the gentleman's rifle cross farther out?

Probably not. Assuming you are working in the velocity range for the rifle - I don't think HendrikNZ is at a velocity below 2000fps - recoil uncrosses barrels. Velocity crosses them. But changing powders is a bit of a crap shoot, with sometimes contradictory results.

If you mount a set of barrels in a vice with the sights aimed at a target, the right barrel will point down and left of the target, the left barrel down and right. In recoil, the right barrel travels in an arch up and to the right. (Since the barrel is off center to the right the torque will cause it to recoil to the right.) Vice versa for the left barrel. More recoil will cause the right barrel to come up and to the right more and faster, the left to come up and left more and faster, uncrossing the barrels.

But with the same or different powder, the recoil gain is somewhat negated when velocity is increased, since barrel time, the time the bullet takes to travel the bore, is reduced, and the bullet exits the muzzle quicker, ie, earlier in the recoil arch.

The trick is finding the right powder and the right amount of that powder to produce the velocity desired with the recoil required to uncross the barrels and with barrel time correct so that the bullets leave the muzzles when the respective barrels are parrallel to the original line of sight to the target. So you are working with two variables which both change when you change one. They don't change at the same rate, thank God.

With a given powder in its sweet spot in any rifle, velocity will increase at a rate faster than recoil.

Elevation is changed after the barrels are shooting parrallel, either up or down as required to bring the POA between the barrel groups. Elevation change is a breeze compared to finding loads, just change out the front bead for a higher or lower one.

Here HendrikNZ appears to be shooting crossing at under 2000fps. Too low velocity I think. But more velocity gained by adding more of the powder he is using - assuming that it is safe - will only cause more crossing, because recoil increases at a slower rate. He needs more recoil to uncross his barrels so he can add velocity. Changing to a slower powder will add recoil at the same velocity, uncrossing his barrels, so he should be able to add velocity as well. But which powder? That is the big Q.

JPK

quote:

Originally posted by J D:
Try 96gr of h4350 then 98gr quit when you near 2150. It may shoot apart with these loads. Some doubles will shoot apart then cross and shoot apart again with different loads of the same powder. Check with your chrno to make sure you don't start pushing to hard. I also had good luck with rl19.I like 2 targets side by side one for the right barrel and one for the left.Call your shots and mark them on a scratch pad. With two targets it easier to see how each barrel is grouping and if loads are crossing the point of aim. Doubles are hard to shoot for accuracy, slower lock time, hard kicking loads, a twisting during recoil,and heavier triggers than bolt guns. How you react to the recoil each time is important with a double rifle.
You got to try to hold them the same each time.
A standing rest or good sticks are better than using a bench rest type set up even when you hold the forearm and rest your hand on the bench rest it self.


JD

That was explained a whole lot better than I could.

At 25 yards I can't tell from the photo's what the loads are doing. He is shooting a 1.5" to 2" group with neither barrel shooting a cluster. When I do my part my Merkel will do at 75 what his is doing at 25. I think he needs to move back and work on shooting tec and make sure of what he is getting.

JD

J D,

I understood what you were saying.

Rereading our friend DUK's post, I think he did too, at least to a point, since he wrote, "... wouldn't a larger load of a slower powder intended to reach the same velocity not generate a sufficiently higher recoil (due to it's larger accellerated total mass) to make the gentleman's rifle cross farther out?" The key being "cross farther out?"

I agree that the 25yd groups leave something to be desired, but if HendrikNZ would move out to 50yds or meters I think he would see the R/L group overlap (currently) or spread (when he switches to a slower powder) better. At least well enough to be useful.

A proper standing bench would go a LONG way to shooting better groups as well, without getting the snot beat out of him.

Personally, I develop loads at 50yds. At 25yds, there is just not enough difference between R/L groups to see much. At 100yds, my eyes are the limitation. So I develop at 50 and on a good day, when my eyes seem to be seeing better (probably due to good strong sunlight and no wind to annoy my contacts) I shoot longer to ensure that my loads shoot to regulation.

I hate loads that spread, since the best group you'll shoot is right off the muzzles and it will get worse from there out. So with open sighted big bores I favor loads that slightly cross, crossing at about 75yds or so. That would give the theoretical perfectly shot group from the theoretical perfect rifle a composite group with a spread equal to the spread between the muzzles at 150yds. That is as far as I'll shoot something that deserves to be shot with a big bore double rifle.

With a scoped medium bore, and I have but one, a 375H&H, I want the perfect load shooting parrallel til the bullets hit the dirt. But, with my bias against spreading loads, I err on the crossing side, and I'm happy with a group where R & L are indistinguishable at 100yds.

Do you have a preference?

JPK

What makes double so interesting is this whole process.

If you think about it, they weigh more and they twist during recoil, they kick harder,and tend to be a lot less accurate than a bolt gun. Shooting the same weight bullet at the same fps ,they hit their max load a lot sooner, and cost a lot more money to buy. They are more delicate and harder to set up with optics.

Until you have shot one you have to wonder why we bother.. They are killing machines, nothing comes up faster and on target like a well set up double. When you are in close and it more important how it handles at arms length,or 25 yards than it does at a 100. They are hard to beat. If you need a hard hitter with a quick follow up they are hard to beat. I am just as fast with my 505 on the first shot, but I have fired my second barrel and ejected my empties before I can eject my fired case of the first round of the 505,I hope to get faster but for now its no contest.

JD