7mm Backcountry Reloading dies and data is now available.

Sundodger

WKR
Joined
May 7, 2013
Messages
382
Location
Washington
Interesting seeing some the load data... I have not shot nor own a 7BC but have been interested in seeing new case material impacts on ballistics. That said, some of the speeds are a bit slower than I would have expected. Granted a 20"barrel vs a 22" barrel, but with factory 170 terminal ascents with a 22" 7 PRC, I'm mid to upper 2900s and over 3k if the weather is in the 80s with the same bullet. 2" of barrel removed is cool, but max 7BC speeds with that same bullet are roughly the same speeds.

I do think newer materials are the way of the future tho and the argument of the 7BC to me is that they are getting magnum speeds with standard bolt face and less capacity... Is this just that less energy is lost and more pressure is being created by stiffer brass?
 
Interesting seeing some the load data... I have not shot nor own a 7BC but have been interested in seeing new case material impacts on ballistics. That said, some of the speeds are a bit slower than I would have expected. Granted a 20"barrel vs a 22" barrel, but with factory 170 terminal ascents with a 22" 7 PRC, I'm mid to upper 2900s and over 3k if the weather is in the 80s with the same bullet. 2" of barrel removed is cool, but max 7BC speeds with that same bullet are roughly the same speeds.

I do think newer materials are the way of the future tho and the argument of the 7BC to me is that they are getting magnum speeds with standard bolt face and less capacity... Is this just that less energy is lost and more pressure is being created by stiffer brass?

They are getting magnum speeds with less powder burned which means less recoil and muzzle blast for same velocity. Having a standard bolt face means there is less bolt thrust. The higher pressures are just a biproduct of the powder burn rate, charge weight, case volume, and bullet used. Compare the load data in the above table to hodgdon 280AI data with same powders. 280AI case might be a hair bigger than the 7BC but the published charge weights are 2-3 grains heavier in the 7 BC.

The thing that stands out to me with that published 7BC load data is that the only powders listed are the absolutely highest performing velocity powders. Not a single more "stable" powder that you'd commonly see in precision rifle disciplines.
 
I am very curious as to what powders they are loading in their factory ammo. One thing I did notice their published reload data is a bit under what the advertised speeds are for their factory ammo in 20" barrels, and like wind gypsy said those were some pretty reactive powders.

I hoped they worked with powder suppliers to develop new powders for this high pressure application that were stable and maybe they did, but are not ready to release these to the reloading community. Which would be a huge mistake IMO.
 
My recollection from when the 7BC came out is that it would require somewhat unique reloading steps, which I assumed involved multiple passes in a resizing die. Anyone have any information on what is involved there as far as process?

Lee has this interesting "special note" on their die listing, which I interpret as saying you're going to have trouble at some point:

Special note: steel cases require substantial effort to full length resize. Be sure you’re using ample, high performance case lubricant like our Lee Resizing Lubricant. When sizing, once the effort becomes extreme, remove the case and redistribute the lubricant, re-insert the case and size to completion.
 
I hoped they worked with powder suppliers to develop new powders for this high pressure application that were stable and maybe they did, but are not ready to release these to the reloading community. Which would be a huge mistake IMO.
I assume they have some proprietary powder blend that won't be released as a canister grade powder. I think Hornady did this with the RCMs if memory serves, though I'll admit I never shot or reloaded for them. I agree with you it would be a mistake in that I'm less likely to buy-in if I have to use Superformance-like powders to get the advertised velocities, but I just don't think reloaders are their target consumer for this cartridge.
 
I assume they have some proprietary powder blend that won't be released as a canister grade powder. I think Hornady did this with the RCMs if memory serves, though I'll admit I never shot or reloaded for them. I agree with you it would be a mistake in that I'm less likely to buy-in if I have to use Superformance-like powders to get the advertised velocities, but I just don't think reloaders are their target consumer for this cartridge.

I agree this round doesn't seem to be targeted at reloaders, and that's a fine choice to make, but I am worried they are not meeting a minimum bar for adoption.


I suspect they are chasing some short term gains (monopolizing proprietary powder for factory ammo), to sacrifice long term gains (the cartridge becomes the new 7mm RM).


If one wants to create the next 6.5 Creedmoor, and all the money that goes along with that, they need widespread adoption and that includes reloaders even if they are not the prime consumer.


What seems very short sighted is how they released it all. If they had released the dies, reloading data (with equal performance to factory ammo), and the cartridge all at once this thing would have a lot less critics.
 
Some of those loads including charge weight are right at the same for a 7 SAUM. I didn't look in depth but just a few at a quick glance so I might be missing some. One that stuck out was the 175gn and N560. Virtually the same performance and powder charge as a 7 SAUM with a Berger 180 HYB.
 
Yeah, I enjoy resizing brass so much that I wanna’ run all my pieces several times to get lube “appropriately distributed”….

Another gimmicky flash in the pan. Pass the Creedmoor/ x47 Lapua cases and hold the fluff.
 
I agree this round doesn't seem to be targeted at reloaders, and that's a fine choice to make, but I am worried they are not meeting a minimum bar for adoption.


I suspect they are chasing some short term gains (monopolizing proprietary powder for factory ammo), to sacrifice long term gains (the cartridge becomes the new 7mm RM).


If one wants to create the next 6.5 Creedmoor, and all the money that goes along with that, they need widespread adoption and that includes reloaders even if they are not the prime consumer.


What seems very short sighted is how they released it all. If they had released the dies, reloading data (with equal performance to factory ammo), and the cartridge all at once this thing would have a lot less critics.
Of course they are not targeting reloaders. Federal is owned by CSG, and all they (Federal) make is ammo. CSG has 100 companies, and 14000 employees, with 10 ammo brands under their umbrella.
From their website:
CSG's main industries are defence and security, automotive, aerospace and rail. The product portfolio is extremely diverse and includes heavy off-road vehicles, radars, air traffic control systems, ammunition of all calibers and luxury wristwatches. New 21st century breakthrough technologies are gradually being integrated into CSG products.


 
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