Graybeard Outdoors - View Single Post - The 24 Mamba Project
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post #42 of (permalink) Old 10-23-2018, 01:44 AM Thread Starter
briannmilewis
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Join Date: Apr 2008
Location: California
Posts: 1,611
Default 24 Mamba AR..Say what?

In an off-shoot of the 24 Mamba project, here is a preview of what team member George in AZ has in mind.

"High BC's are in! Which = heavy for caliber bullets.

My plan for the 24 Mamba AR is a combination of short chambering and seating bullets deeper. As for how it all pans out, we'll hopefully find out before Christmas.

I ordered 2 x 24" blanks (1:8 twist) but I still need to save up for extensions, a required part for AR barrels where the bolt locks up.

Goal #1: Achieve a respectable velocity.

One unfortunate part of doing the 24 Mamba AR, is by being confined to a 2.3" cartridge length, a great deal of the case capacity is going to be consumed by having to seat the bullets deeper.

However, by utilizing high BC bullets it retains velocity longer and makes up for it on the big end. My benchmark is 2450 ft/sec from a 18" barrel with the 105gr bullet.
If I do this it will put the 24 Mamba AR in the same playing field as the 6.5 grendel which has long been the benchmark of long range/do all cartridges for the platform.

Goal #2: Accuracy

The second biproduct of the 24 Mamba AR is exaggerated bullet jump due to having to seat the bullet further in the case. This may or may not effect accuracy.

Some bullets are sensitive to excessive jump and some like it. Worst case scenario is I can buy a reamer with the correct throating if I meet/exceed my velocity benchmark. But I may get lucky and everything pans out with what we have."

Good luck George.
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