6.5mm Creedmore

The gentleman I was shooting with on Monday brought a couple of interesting firearms.

One was a pistol caliber carbine which was a hoot-to-shoot. I am not sure what it is good for but it was fun. One thing I struggled with were the sights. The front sight was a very narrow blade and there was not much contrast between it and the knot on the mottled, splotched log I was using as a target. The mission determines the best sight package and I am not sure about the target. If the mission was for home-defense, a shake-awake red-dot might be a good choice.

The other weapon he brought was a 6.5mm Creedmore. He hadn't planned on buying it, but....there it was.

For a time, during the throes of supply-chain constraints and not enough workers, the major manufacturers set the equipment to pump out 6.5mm Creedmore and just kept running the equipment. Every change in product results in lost production because of the need to validate settings. If you can sell every unit you make cranking out 6.5mm Creedmore, it is irresponsible to stop production and lose revenue.

Reloading

Yeah, I need to add another chambering to my inventory like I need another hole in my head, especially if it requires another powder.

Hornday #2620, max velocity 6.5 Creedmore, trajectory, deviation from line-of-sight.

I have IMR 4895 in stock but what about the powders that are more in alignment with the cartridge's volume, bullet weights and expansion ratios? What do I give up by using what I already have?

Looking at velocity, I lose 200 feet-per-second verse the "best" powders like Winchester Staball 6.5 and 100 feet-per-second verse "better" powders like Ramshot Big Game. What does that mean in the real world?

One of the first questions involves trajectory. Will cognitive and physical skills of the shooter be overwhelmed by the need to compute Kentucky-windage, and as a result of those demands miss the intended target.

For a regular hunter, shooting at coyote-sized targets out to 250 yards...it means almost nothing according the the Hornday Ballistic Calculator.

Terminal performance

How about the effect of the bullet after it impacts the target. The bullet's propensity to expand is VERY dependent upon the impact velocity. 

According to the Hornday Ballistic Calculator, an additional 100fps in launch speed for a 0.264", 129gr, flat-base Interlock translates into another 50 yards of range vis-a-vis impact velocity. Even launched at an anemic 2670fps, the 129gr, Interlock softpoint will still be within its design envelop at 250 yards and should expand.

Paradoxically, rifle bullets penetrate more deeply when the impact velocity is at the lower end of their design envelop. A bullet that is marginal for elk when the impact velocity is 2800 fps might perform very well when the impact velocity is 2400 fps because it will expand less violently and expend more of its energy more deeply in the target.

An Aside:

When laser range-finders first hit the consumer market, a gun store in Wyoming or Utah challenged customers to guess the distance to the flag-pole in the center of town.

Bear in mind that their customers were hunters and hunted in an region where long shots are possible.

Most of the customers guessed 1/3 mile to 1/2 mile. They were stunned to "range" it and see that it was about 300 yards from the store. Their estimates ranged from 2X to 3X off. Some of them even paced out the distance hoping to prove the laser range-finder was wrong.

A typical white-tail deer at 100 yards looks pretty tiny to most people and they always over-estimate the range. Without a steady-rest, a 200 yard shot at a deer is a very long shot.

End Aside.

So if I find myself cranking out a few 6.5mm Creedmore reloads, it will probably be with IMR 4895. I doubt the coyotes will notice the difference.