msd4141 wrote:Hoot,
I am using once fired Hornady brass. I did not bell the case. I have a caliper, and a micrometer. I checked the crimp with both. .471 to .472 as close to the case mouth as I could get. I am wondering, since I had no powder or primer in the bullets, just dummy rounds, do you think the added weight of those two components would help slow the force of the bolt? I am using JP Enterprise silent captured spring for the bolt carrier. I am going to look to see if I can buy a lower pressure spring. I am running an adjustable gas block, so I might be able to make that work. A lower pressure spring would lessen the driving force of the bolt. The other thing I'm going to do is use a q tip like you were saying to remove any oils in the case and on the bullets, if there was any there. thanks for the response. Marc
I seriously doubt that the added weight of the powder and primer would factor in but you bring up an interesting point about the spring. I've always used a standard rifle spring (A2 Stock) and a
[color=blue]weighted[/blue] bolt carrier to slow things down since I'm not running full auto. You can barely see or hear the difference with the naked eye, but it helped keep the brass from getting as scratched, scraped and generally beat up. I played with an adjustable gas block but never saw much benefit from it so it went on my 6.5 Grendel which did. The 450b is the only caliber I spend a lot of time on, that has such a struggle with neck tension. True, the .451 projectiles have a little steeper hill to climb than the .452. Without a doubt, Neck Tension is the "800-pound gorilla in the room" with regard to reloading challenges in this caliber. I'm still waiting for some member, looking to build on their gravitas here, doing an A/B
Range Day thread between cartridges with sealant (like NATO uses) around the bullets versus none, all else being equal. Both slam chambering immunity, average velocity for a given charge and group size might be interesting.
WRT stab crimping, let me give you a word of caution if you ever go there. I once tried
dual stab crimps, IE one in each of the driving band grooves of the 200 XPB. It definitely immobiled the bullet
to a fault! I did not adjust my recipe downward in anticipation of higher pressure and it only took two shots with the lowest charge weight in the ladder, to convince me to abort the experiment. It felt like a (barely) controlled explosion the first shot and this is where "gene pool cleansing" lurks. Like a fool I figured it was a bad reload and shot again. Same result!
RED LIGHT! I spent that evening pulling down a lot of loads I had prepared for the test. Luckily, monolithic copper bullets don't deform like jacketed lead ones do, once they've been loaded, so I was able to reuse the bullets, which constituted a significant chunk of change. When I pull down a load, if I can see any deformity in the bullets, either from general neck tension or a ring from the taper crimp, they go in the recycle box. Life's too short for wasting my time using deformed bullets, as I've found that the
consistency of performance goes out the window. I actually have a BR caliber wood stock with about a pound of them stuffed in the butt for additional weight. A better value than buying a lead stock weight or sacrificing shot shells. Yeah ole Hoot's weird that way.
Hoot