Does anyone know what the case capacity is for the 700 BMG Improved using the 1000gr bullet? What powder is being used? When I spoke with a gunsmith about it he stated that he sells them without a muzzle brake to his customers. What would be the most effective muzzle brake for this round?

You must be talking to Dennis Olson as I know he has built at least one 700 Improved on the Mcmillan repeater action. Dennis even did it as a pseudo drop box in a walnut stock. All of these are wildcats and thus their dimensions will change slightly. From studying this case extensively, however, I doubt that the case capacity is more than 5%-8% greater than the box stock .50 BMG. However, given the bullet diameter, and about 240 grs of 24N49 I'm told it's easy to exceed 3000 fps with a 1000 gr bullet.
Remember that unless the gun weighs 40 lbs or more, with no brake this thing has the potential to kick you senseless. The original designer of the .700 Improved Monte Kyser, told me the .700's recoil was brutal and I believe he used a Custom break. This info, I believe, is all available at the FCSA website. Personally, despite the looks I'd go for a clam shell break due to their effectiveness. Unfortunately, it would have to be a custom clam shell as their would be no cone left on a standard .50 clamshell once bored to .740. george Vias also makes a very effective break that should work well.-Rob

Thanks for responding Rob. Yes, you are correct in that the 'smith I spoke with was Dennis Olsen. He seemed a bit surprised when I inquired about the type of brake he used. I tried the FCSA website and it is undergoing some changes so the information is not there. Is the 700 Improved covered in the two part series of BMG wildcats by Monte Kyser (2000 edition)? What barrel length is providing 3000fps? Does this round require ATF approval or is it considered the same as the 700 Nitro?

Robgunbuilder and M.R.CLEAN...!

Please give me the adress to FCSA web site...?

What weight would it be on a .700 BMG with a muzzle brake..??

Thanks...!

Try www.FCSA.org. I have a copy of the articles and you can order them from FCSA. It is uncertain how the .700 Improved is classified by BATF. It certainly is a wildcat not designed as or used in any existing military weopon. Thus, it truly falls under the category of a sporting cartridge. The BATF won't provide a clear answer and in fact I don't believe they really know the answer. It is illegal in Kalifornia due to the bore size, although how they can make that distinction and still allow 12 Guage rifled slug guns escapes me. I know a number of folks who have built them and had no problems.-rob

Rob...

That adress does not work... do you know any other adresses to FCSA???

Sorry. It works...

Robgunbuilder..!

The .700 BMG get 3000 f/s with 240 grain powder.
And the 700 NE get 2440 f/s with 250 grain powder. Is it different powders to .700 NE and .700 BMG or is it the barrel lenght

How long is the barrel in a .700 BMG...???

Thanks...!

Robgunbuilder.

How long was the barrel on that .700 BMG that Dennis Olsen built...? And does the 24N49 powder give higer pressure than the powders that you use in the .700 NE...?

Thanks...