ltdmstr

We used N320 for .40 SW back when the UPSA major power factor minimum was 175. Never had any problems. I believe the load was 5.4g at 1.200".

Unfortunately, NRA isn't what it used to be. Not even close. I spent about 10 years on the board of directors of a large private club (2k+ members) with multiple ranges/disciplines, and NRA was very helpful in designing upgrades to our rifle and shotgun ranges. But, that was 15+ years ago.

If you're designing from scratch, this might be helpful Probably worth the $54. The NRA Range Source Book (Current Edition) is a technical source book for shooting range builders and operators. With 27 chapters of information on range operation and construction collected for you in a three-ring binder. The updated version of the NRA Source Book includes both information on Outdoor and Indoor Ranges, an extensive vendors list of those in the industry able to assist with the building or improvements to your range, as well as a section for general drawings for reference. https://materials.nrahq.org/index.php?route=product/product&path=91_113&product_id=404

Is that a new thing? I've been using N320 since they started importing it 20+ years ago, and never seen green powder.

Sorry guys, major brain fart on my part. And you're are absolutely right. Revolver rounds get longer not shorter. Back when I used to shoot at public ranges, one time a guy showed up in the stall next to me with a Ruger Super Redhawk in something like 454 Casull or 480. Figured I didn't need to be around for that, so started packing up. He fired one round and the cylinder locked up.

Crimp for revolver rounds is completely different from semi-auto. Revolver rounds, especially for magnum loads, typically use a roll crimp to prevent setback from recoil. That's why revolver bullets often have a cannelure. Semi-autos use a taper crimp and rely on adequate case sizing to prevent setback. What's shown in the pictures above is perfectly fine and will make no difference in accuracy.

Yeah, but one's a true custom gun built the way you want it, and the other is production gun, with basically no options. I know which one I'd pick. And it's not a close call.

If you look at the SAMMI recoil formula, the only thing that changes felt recoil for a given bullet weight is the burn rate of the powder. Also, heavier bullets require a smaller powder charge. These two facts back up what's widely acknowledged; that the combination of heavy bullet and fast powder results in the least felt recoil for a given power factor. At least for a non-compensated gun. As for what to shoot, some heavy bullet combos get to the point that they actually feel sluggish. Some folks actually prefer lighter bullets for a more snappy recoil and faster return to target. It's all personal preference and what works for you.

Well, it's not like he can put the material back and start over.

So along with doing away with the power factor requirement, we should do away with the "practical" element as well?

Low ports, prone, and shoot thru barrels were very common back in the day. Also, timed standards. Single stack nationals used to have timed 50 yard strings.

This is correct. Those advocating minor only seem to ignore the fact that power factors for most 9mm defensive ammo is way above USPSA minor. And by a significant amount. Most are in the range of 150, and some are even higher than that. No doubt bullet design and shot placement help bring 9mm closer to 40 and 45 in terms of real world performance. But the amount of kinetic energy (a factor of velocity and mass) impacting the target will always be a key factor.

Point is, it hardly matters with minor pf and a dot. Basically, it's a foot race/obstacle course where you pop off some rounds along the way. Really not much different than SASS. And with the growing contingent of LARP types, it's basically turning into SASS for the tacticool crowd.

Let's just do away with power factor requirement all together and make all the targets 7-10 yards. Like SASS. Seems like that's where things are heading anyway.