470 Nitro Express Merkel Report: Final Installment

06 May 2002, 19:50

24 more rounds were fired today, through the 23.6" Merkel barrels.

4 each of 6 different bullets were tested, all with the same 92.0 grains of RL-15 in Norma brass, F215 primer, 1/2" to 5/8" packing foam plug as filler, chronographed 15 feet from the muzzle, average velocity, extreme spread of velocities, and composite group size, crossing and elevation issues were noted.

Surprisingly, all composite groups were 3" or less at 50 yards. Only one bullet, the GS Custom HV, raised the center of the composite group about one inch at 50 yards. All the others followed a similar pattern around the bullseye: Velocities much over approximately 2080fps have the right and left barrel crossing at fifty yards, but not by much, just about all the bullets were within 1.5" of the bullseye, horizontally and vertically.

My cheap and reliable chronograph was the "Pro-Chrono Plus."

No case head expansion was measurable. They all stayed the same resized 0.569". All brass dumped easily out of the chambers, and primers looked mild.

My best groups heretofore have not been bettered.

Recapping the Federal Factory loads:

Woodleigh Weldcore soft 500 grains
2056 fps
ES 53 fps
group (composite of 4 shots at 50 yards): 2"

Trophy Bonded Sledge Hammer solid 500 grains
2084 fps
ES 73 fps
group: 2.5" by me, however the Merkel Factory target showed 1.6" at 50 meters (with TBSH Federal load reportedly), thus surpassing, barely, my best hand load with the Weldcores in 1.6" at 50 yards. They must have been rolling their own.(?)

And now the hand loaded bullets tried at 92.0 grains of RL-15:

Woodleigh Weldcore soft 500 grains
2083 fps
ES 18 fps
group: 1.6"

Woodleigh FMJ/"solid" 500 grains
2115 fps
ES 20 fps
group: 2-3/8"

GSC FN 500 grains
2095 fps
ES 23 fps
group: 2-1/2"

GSC HV 500 grains
2164 fps
ES 19 fps
group: 2-3/8"

Swift A-Frame 500 grains
2120 fps
ES 32 fps
Group 2-3/4"

Hornady XTP 400 grains (handgun bullet)
2203 fps
ES 26 fps
group: 3"

Barnes XLC 500 grains
2141 fps
ES 23 fps
group: 2-1/8"

Another observation on how case capacity affects things: The GSC FN is very close to 1.4" long. The GSC HV is just over 1.6" long. The FN velocity was 2095 fps, while the HV velocity was 2164 fps. They both have eight driving bands and the same bearing surface. When both are seated to the same COL, the HV crowds the case and ups the velocity. Likewise the roomier Norma brass requires more powder than the heavier BELL brass to generate the same pressures, all else being equal.

Right left, right left, there it is.

Conclusion: I have made a good start on breaking in the Merkel. If I run out of factory ammo, I can roll my own. The purpose of the above was to establish velocities with various bullets. I or someone else might get better accuracy with more concentration on groups with a particular bullet, or tailoring the powder charge to that bullet.

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RAB

06 May 2002, 20:38

<Rusty>

Looks like you got a shooter!

I love to see someone else get good results with RL-15. Very consistant velocities as your report shows!

Rusty
We band of brothers!

07 May 2002, 01:27

Kanatak

Thanks again DaggaRon for posting your load-test results. I feel like I have a template to work from when I begin my shooting in June. A kind gentleman from this forum is sending me a 50 BMG case for filler cutting purposes and have all my components in place. I will let you know how I progress.

Many thanks again for sharing your experience.

07 May 2002, 03:07

<Terry P>

Thanks RAB,
Interesting posts on the 470NE.
Terry

07 May 2002, 03:49

fredj338

Interesting, it looks like you've confirmed that the 400gr Hornady will shoot close enough to POA to use as a light practice round. Well done!

07 May 2002, 08:24

RIP

Thanks guys. I have a hunch that dropping the velocity of all the faster bullets to 2080-2085 fps might make them shoot better groups, in my rifle. However, all of the above loads look good enough to find some use, in my rifle.

Everyone ought to start from scratch and work up with their rifle and brass selection. 85 grains of RL-15 and a filler would probably be a good place to start with 500 grain bullets. I really don't know the difference betweeen the GM215M and F215 primers, but the F215 seems to be the primer to use.

I violated some rules in going right to my max load with the new bullets, but I felt that I could, having already worked with the Woodleigh softs and solids some, and the Merkel is certainly stout enough for a little flirtation.

BELL Brass would let me use less powder, in my rifle, IMHO.

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RAB

07 May 2002, 08:42

RIP

PS: All the above loads were crimped, all bullets had cannelures.

Working with a double makes one appreciate them for what they are, close and quick handling stoppers. It also makes one appreciate how powerful and accurate a scoped bolt action can be by comparison.

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RAB

07 May 2002, 12:34

BigB

DaggaRon,

Is the packing foam filler you use a ridgid type or a spongy type foam. Also are you using RCBS dies or ?

So which load will you use in Africa and when does that Merkel get to shoot at something other than paper.

BigB

[This message has been edited by BigB (edited 05-07-2002).]

07 May 2002, 18:55

RIP

BigB,

Soft and springy foam, tough and light weight "packing foam." Not styrofoam, as it is stiff, crumbly, and non-resilient.

Yes, RCBS dies, ordered from Huntington.

If I were limited to one bullet for African game: GSC FN. That would surely let the light inside any carcass. I would play around with charges before finalizing the powder.

I will probably just do some deer and wild boar hunting in Kentucky and Tennessee with it first. I feel it is accurate and "ballistic" enough for plains game to 150 yards, and dangerous game within 50 yards.

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RAB

27 May 2002, 10:05

RIP

Brought back by popular demand.

27 May 2002, 11:37

Atkinson

Sounds like a winner, I like the Merkel, only I (like you), would only have one in a rimmed caliber and that is the 470 in this case...a fine caliber..The gun feels good to me and handles well.

27 May 2002, 11:46

RIP

Ray,
Honesty is all we ask for, eh? I will have to book my next trip through your agency.

27 May 2002, 16:12

JBoutfishn

All of your detail is really appreciated. I have added all your loads into my "black book". As I stated in previous post, I am using Bell Brass in the Krieghoff 470, and find that overall results track very close right down to reducing loads due to the heavier bell brass.

Thanks,

Jim

28 May 2002, 04:18

MacD37

Very well done, DaggaRon! [Smile]

This is one of the best demonstrations of load work up, for a double rifle, posted on the net I've seen. The Merkel seems to be very accurate with a number of bullets, useing the RL15/F215. One thing I would do, now that you know all the bullets will shoot in your rifle,is find the two loads the work to the same point of aim with your favorite solid, and soft, and load up 100 rounds of each in NEW brass, and store away. I do this so that if a cull, or cancelation comes up on the spur of the moment, I can grab my passport, and rifle/ammo and move. There is nothing like haveing to scour the contry side looking for ammo, and haveing to take what ever I can get, or turn the hunt down. [Frown]

Your Merkel seems to follow the accuracy I have gotten with mine, and the same as most of the people, I've talked to, who shoot one in any chambering. These little devils just plain shoot! Mine is a small chambering, but it shoots better than some of my doubles that cost three times as much. [Big Grin]