Federal New Cartridge

[walk2112]

Geissele just came out with a bolt gun chambered in 7BC and they're claiming far less than 1 MOA groups. If they were able to get this accuracy with this cartridge, it would be intrigueing, and the best accuracy we've seen on the interwebs yet. Typical geiselle pricing, north of 3k.....

I know this topic and argument is tired, but I also wonder how they define and measure a ‘group’ (shot count)

 

[mustelid_master]

I know this topic and argument is tired, but I also wonder how they define and measure a ‘group’ (shot count)

It is certainly worth asking. I believe they mentioned three shot groups in the video

 

[cowboy300]

I talked with an industry insider yesterday that was part of the initial testing of the 7 backcountry before it was released. They haven’t seen very good accuracy and also blew up a ti can on 20” barrel. I would strongly recommend if you are planning on using a suppressor you check with the manufacturer and stick with steel. The early federal ammo boxes that were sent to test had the pressure test data labeled on the box and it was 92000 psi on one lot.

 

[wyosam]

I am At sheep show this weekend and talked to the guy at the federal booth. He said that within the next 2 months we should see specific info coming out about reloading the 7BC. He said they are waiting to release all
Info at one time regarding dies and reloading the cases and everything else. He also said that it would be a 1 step pass through the dies and would not require any additional steps as I understood it but I had been drinking most of the day so forgive me
If I missed something. Just being honest

He also said they would be selling cases for reloaders as long as availability was available. And they are getting 7+ reloads from the cases without issue and are using standard large rifle primers


Obviously this is coming from a guy that was sent by federal to talk specifically about the 7BC because that’s what mainly was at the small booth so take that with a grain of salt but wanted to share.

Im not sure if I’ll go back to the show tomorrow as I seen everything I was looking for but if I do go back let me know if anyone has any questions they would like asked

It will be interesting to see what they came up with for single pass sizing. A sizing die isn’t rocket science and RCBS has been at it quite a while now. Seems like maybe voodoo, magic, and trying to put out sales-affecting fires might be involved.


Sent from my iPhone using Tapatalk

 

[BelowAverageBowhunter]

1..All actions are pressure test well beyond the 80 that would be a new cartridge. Hell I think I remember some said they tested them well above 100.

2. I am having trouble understanding the magnum bolt face problem you alluded too. F = P × A. I think that is right. Logic would dictate that if F which is bolt thrust and P which is pressure you would see an increase in P you will see an increase in the other. So the 7 MM BC does increase blot thrust.

You're correct on F=PxA

so if we take a standard bolt face pi(0.473/2)^2 * 80,000psi = 14,056 lbs of bolt thrust

a magnum bolt head pi(.532/2)^2 * 65,000psi=14,450 lbs of bolt thrust

Those are a little bit simplified because you should probably use the internal case diameter during firing not the bolt face diameter but those are awfully similar for it to be by accident. A magnum bolt face at 80,000psi would be 17,784lbs of bolt thrust. Almost all actions can probably take that but they design a safety factor into that that may not fly when you add 25% to the load.

 

[gerry35]

My favorite thing about the gun community. Everyone screams for innovation but when companies innovate the idea gets poo-poohed before it even hits the market.

Too many guys had an opinion on something they know nothing about.

 

[gerry35]

I'm not interested in a 7mm but find this a really interesting concept. Would seriously look at some kind of a 257 or 277 version.