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VMFn542bob 04-15-2012 11:03 AM

A MANN Accuracy Device for the 7.62 x 54R
The 7.6254mmR is still in use by the Russian military but the "R" in the modern official C.I.P. (Permanent International Commission for Firearms Testing) designation (7.62 54 R) stands for Rimmed, in line with standard C.I.P. designations.
This is one of many MANN barrels that will probably never be turned over the the CMP. A MANN barrel is a testing machine with many uses. I believe it is highly educational to see how MANN barrels are used so I will contunue to post relevant links on this subject.
Temperature Compensated Loading Curves for the 7.62 x 54R Armor Piercing Incendiary (API) Round
The purpose of this testing was to learn which variables were statistically significant in controlling the velocity of the 7.62 x 54R API round.

kraigwy 04-15-2012 11:26 AM

I find that interesting, regarding the temperature changing velocity. We know that every 15 degrees change in temperature changed you bullet impact 1 MOA.

I did some testing a while back regarding High Power rifle shooting. After the barrel/chamber got hot, the difference in velocity of the round if, for say you chambered the round while waiting for target repair (scoring and pasting) and loading the round after the target comes up and the instant before you shoot.

I don't know what I did with my notes, but I do remember there was a difference in velocity.

Thanks for posting that link, it kind of explains what I did.

VMFn542bob 04-15-2012 02:13 PM


Originally Posted by kraigwy (Post 577944)
The Remington Action on the Mann device doen't have a recoil lug.

How does that affect the device and how would one put it in a stock???

I don't want to do any modifications to the action/device itself.

PM sent

kraigwy 04-16-2012 11:08 PM

I just found a pretty good description of the use of the Mann Device in Hatcher's "Textbook of Pistols and Revolvers", 1935.

I don't want to post the whole thing as I don't know who owns the copyright.

Anyway, a V shaped metal trough of steel is mounted on a concrete base. Elevation and Wind age screws are fixed to the trough.

A telescope is laid into the trough to get the trough "sighted in" then removed.

The heavy Mann Barrel (Hatcher calls it a cylindrical barrel) is laid in bottom of the V trough. Under recoil the Mann Barrel moves but the trough doesn't. For the next shot the Mann Barrel is laid back in the V, which automatically lines it up for the next shot.

The trigger is activated remotely of course.

Simple enough.

jerryjeff 04-18-2012 02:18 AM

Wow, that is some real interesting history. A real scientist dedicated to learning.

kraigwy 04-18-2012 08:29 AM

Yes, Doctor Mann decated his life trying to find out why, if everything is consistant, a two or more bullets wont go into the same hole down range.

Something we are all looking for.

Radtoy 09-04-2012 10:14 PM

So... How does it work?
Does the device come with an adequate receiver? Is it mostly a matter of finding a stock then mounting a scope on it? What would I need to set one set-up as a reliable rifle? It sounds like something to take to a 1000yd range and see what I can nail at different distances. :)

kraigwy 09-04-2012 11:32 PM

Depends on what action you have.

For my Remington Action, I put on a fiberglass stock. I couldn't inlet the barrel because the stock I found wasn't wide enough. I ended up having to cut it off just in front of the action. Looks rather silly but it works.

This is a temp. fix for me while I figure out what sort of vice I want to build to use the device as intended.

BUT, it shoots, Any thing you rest the barrel on such as aiming sticks, bags, etc should be placed as close to the action as possible. Taking that into consideration, I believe you can use it for a F-Class rifle. You'd want a better scope then I put on this one.

I wanted to use it to develope loads for High Power w/ my White Oak Upper. It does do that.

I suppose if you wanted you could build yourself a stock that would fit the barrel. I may do that some day.

VMFn542bob 09-05-2012 03:14 PM


Originally Posted by Radtoy (Post 661199)
Does the device come with an adequate receiver? Is it mostly a matter of finding a stock then mounting a scope on it? What would I need to set one set-up as a reliable rifle? It sounds like something to take to a 1000yd range and see what I can nail at different distances. :)

Like Kraig said, it depends on what MANN rifle you have. His MANN rifle is rare, chambered for the 5.5645mm NATO (.223) and so far, it's the only one. Also his has a receiver that was made for attaching a scope.
The MANN rifles the CMP still has for sale I believe are all chambered for 7.62x51mm NATO (.308). They come with a receiver, probably a mixed variety of 1903-A3 manufacturers, and a bolt. The device has been headspaced for testing NATO ammunition (ZERO head space) and the bolt, will have the receiver serial number engraved on it (at least those I have seen that came from the CMP do).
1903-A3 receivers have a dove tail for a rear sight (the rear sight is not included with the MANN) but the dove tail is not appropriate for attaching any kind of scope that I know of. The rifle also comes with a sawed off scant stock, leaving only the pistol grip portion to embrace the receiver.
Keep in mind what this was used for and how it was used.
With exception to Kraigs unique 5.56 MANN, all of those who have turned these into a bench rifle have employed the services of a gun smith. In every case I know of the gun was altered to accept commercial ammunition and modifications were made to attach a scope and stock.
So far, the only MANN rifles I have heard of that were made into a bench rest rifle were the 30-06 MANN (no longer avaiable from the CMP), the 7.62x51mm NATO MANN currently available, and Kraigs 5.56mm MANN which be bought at the CMP Auction.
My MANN project takes a different approach.
There will be no gun smiths involved and no modifications made to the MANN.
It is a drop-it-in and shoot it approach.

VMFn542bob 10-22-2012 09:16 PM

Unusual MANN testing devices
The 40mm Grenade MANN Testing Platform
Development of a 40mm Mann Barrel System for both High and Low Velocity Ammunition

25mm Bushmaster Gun Barrel Coatings MANN Testing Platform
Cannon Life Extension Using Explosive Bonding
Ta-10W Lined M242 25mm Bushmaster Barrel
Technical Report ARMET-TR-08001
Michael Ellis - May 2008
Munitions Engineering Technology Center
Picatinny Arsenal, New Jersey
Photo link
Fig. 22 - 25-mm Mann barrel test setup at ARDEC indoor test range

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