The 7mm merrill ??

S

SINGLESHOOTER

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Greetings:

I have been searching the WWW for information on the 7MM Merrill such as History, Use, Cartridge Forming and reloading data but, so far... I have been skunked. I thought there would be a reasonable number of articles on this cartridge explaining which parent brass was used to form the case and some load data. There were more than enough firms advertising the dies but, that is all I could drag up. If you know where I can get some good reading info on this Wildcat please pass it along to me.
 
I don't remember what brass was used to make the round but I think it was the same power level as the 7 TCU. you could get extra barrels for it but they had to be fitted first at the factory which was why the TC Contender was used a lot more. It was quite a bit more expensive than a TC. It had a very weak extractor so anybody that shot them also had a "Merrill rod" along with their other gear. the "rod" was nothing more than a cleaning rod and was used to knock out the fired case. another problem that some people didn't like was the grip felt big to most people as compared to the TC. also before it could be fired you had to alter your grip a little bit to push down on the safety with your thumb.
 
I'm been doing some more thinking this and I'm pretty sure it was a rimmed case and the base case was probably the 30-30. Elgin Gates had come up with the 7 mm International Rimmed (made from the 30-30 case)round and I think the 7 mm Merrill would be closer to the power range than the 7 TCU. I have an old Barnes cartridge book and while I know it isn't in that there might be something in the newest version that I have seen in the bookstores. I don't think there was a lot of these pistols made because of reasons that I mentioned. I would think that RCBS or Huntington would probably have the dies or can make them but I don't think they will be cheap.
 
I just checked my big Wildcat Cartridges Vol I and II (Combo Edition) by Wolfe Publishing and couldn't find a thing about it. Also nothing in the Ammo Encyclopedia or Cartridges of the World. An odd caliber for sure.
 
I found in the 1984 "Guns & Ammo Handgun Annual" that the 7 mm Merrill is made from 225 Winchester cases. the only load mentioned was with the 160 grain Sierra rifle bullet (doesn't say if it was the flat base or boattail) with 32 grains of WW-760 powder. this load was good for 1,800 fps in a 14 inch barrel. considering how high the limits were pushed in IHMSA shooting back then (and maybe now for that matter) I would definitely work up to that load. since it is using 225 Winchester cases that could be a another problem in that they probably aren't a current production case. I'm not even sure if 225 ammo is even loaded any more. this case is used in some of the JDJ series of rounds so somebody is getting their brass from somewhere. dies for an odd ball caliber like this are probably going to be expensive. it will probably be closer to the 7 mm BR power wise
 
Quite likely just one of dozens of 7mm wildcats that never caught on, seems to be the nature of wildcats, especially metric ones. If I had one in a rifle I liked I'd have it rechambered to a cartridge I could readily find dies components and reloading data for...but what's the fun in that?
I'd be interested in hearing what you know about it while we're wating for someone more knowledgeable to come along.
 
My reply 2 u guys

Well thanks for the replies and the info, I could not find my post and made the mistake of posting again. Oh Well I'm new and still on the Honeymoon. I figured the 7MM Merrill to be a extinct cartridge when I couldn't find anything in the WWW but die advertisements. The Merrill dies were in a large box of assorted dies given to me some years ago. I also have dies for a 7mm INT-R and, it too seems to be heading for extinction. I have been reloading the 7MM TCU for years now and I am extremely satisfied with the results. I believe its time to advertise the Merrill and the INT-R on ebay or some reloading Sites or maybe have a good friend trim them to another cartridge size...I have no use for either. Thanks again for your support and feedback.
 
the 7 mm TCU is by far the easiest to work with. just expand a 223 case to 7 mm , load it and shoot it. on paper the 7 mm Merrill might have a bit more power but probably not enough to notice in actual use
 
225 Winchester necked up to 7MM. It was made for the original Merril Single Shot Pistols. Keep searching 7MM Merrils as there is some loading info out there.
 
CAUTION: The following post includes loading data not published for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assume any liability for any damage or injury resulting from use of this information.


Here goes a bunch of supposition, but it may not be off by much. A necked up 225 would look like this QuickDESIGN drawing:

attachment.php


You need to verify those dimensions are close with a chamber casting. If the drawing is accurate, then the case should have about 44 to 46 grains overflow water capacity (not literally overflowing; just level with the mouth with no meniscus). In that case QuickLOAD suggests Alliant Reloader 10X will likely be the best powder to try first. With a 120 grain Hornady or Sierra SP bullet at 2.50" COL, the starting load would be about 28 grains of RE10X. The computer puts the maximum load at about 31.5 grains and 2500 fps from a 15" barrel (no idea what you actually have). 130 grain SP's need about a grain less powder at each end and cost you about 80 fps in that barrel length.
 

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Three different threads merged...

In the future, please don't restart a thread on the same subject. It's a handful for us to clean up/streamline the board's discussion.
 
7mm Merrill

This probably isn't needed now but I thought I might as well add it.

The problem with talking about dies for the 7mm Merrill is you have to be concerned regarding "which" 7mm Merrill you're referring to. :) This is STRICTLY relating to the dies.

The "original" 7mm merrill was based on the .225 Win case with a length of 2.030" and data for it can be found in the Accurate Smokeless Powder reloading guide Number One. Pacific made the dies and maybe other die manufacturers also. I currently have an RPM XL pistol with one barrel in this caliber.

Along about 1980-82, Jim Rock made a new 7mm cartridge for his pistol and called it the 7mm Rocket. It had a max case length of 1.700 and a trim to length of 1.690. I had one of these at the time but sold it. I still have the dies for it and they are also made by Pacific and on the die, it says 7mm Merrill FL sizer and 7mm Merrill Seater. Sadly, I have misplaced any reloading data I had for this cartridge.

On the Pacific die box it says Part no. 040862 and shell holder #4 and another stick-on label on the usual Pacific stick-on label that says 7/MM Rocket.

Basically, the rocket is a very slightly more case capacity 7mm version of the .30 herrett cartridge. It's also a very slightly less case capacity version of the 7mm Ultimate Silhouette cartridge currently sold by Eben Brown of www.eabco.com which has a case length of 1.750"

Hope this helps to muddy the waters. :)
 
7mm Merrill brass

I realize this is an old thread but any 7mm Merrill gurus out there?
I have some brass to unload, plastic cases indicate as such but brass is 225 Win.
Anyone know if these can be reshaped to 225 Win or another? I believe they are about 1.93" lg
Pls email nhmikel@yahoo.com
 
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