450Bushmaster.net

Just to weigh in on all of this experimentation and to set some minds at ease.

When you straighten out the last third of the case to the mouth, you aren't going to experience any real problems, one might associate with this process, Vis-à-vis, the extraction, after firing, process.

The example I can site is the 30 Carbine round. The factory fodder is in fact loaded in this fashion, e.g., the last half (not the last third) of that case is in fact "Straight". The reloading dies for that case however, resize the case for a total taper over the entire length of the case.

My personal 45 Professional dies, to this day include, a 45 Colt, 45 ACP, and 45-70 dies.

What I'm trying to say is, ..Don't be spooked by none-traditional loading practices. Your real questions should be, am I getting enough Bullet Pull, so I can burn the powder properly, or I might not care if the powder burn is efficient or not, especially if I can use a better bullet for my intended Mission (This might just be the biggest concern..can I kill the target? Can I retain enough terminal-ballistics, to decide the issue when the bullet gets to the target, be it paper, steel, or flesh). After you decide theses issues, the only thing left and this is Paramount, do I have the correct Head-Space and does the cartridge pass my Thunk Test??

Heck, I even Thunk Test Bottle Necked Cartridges. If you're not doing it then start. Imagine, spending 20 Grand on a hunt, you want to use your Home-Rolls and when you get Afield, you discover your cartridges wont chamber..Oops! From my PH days, I always thunk and then chamber every round I intend to use, for I have seen ruined hunts, over this little matter..

..t

Hey, WC: What do I know, but, I'm thinking this "tightneck" technique might also result in the best speeds when loading Barnes Buster 325s with the standard-length Bushy gas system?

wildcatter wrote:...snip Heck, I even Thunk Test Bottle Necked Cartridges. If you're not doing it then start. Imagine, spending 20 Grand on a hunt, you want to use your Home-Rolls and when you get Afield, you discover your cartridges wont chamber..Oops! ...snip...

..t

Ding Ding Ding!!!

Happened to me with my .300 Win Mag BAR. I hand ejected three rounds before I realized what was wrong. By then, the 6 pointer standing 20 feet from me got bored and sauntered off while I was struggling to get more ammo out of my pocket.

Happy ending though an 8 pointer came in later that day and by then I had thunk tested my remaining ammo. He tasted good!

Hoot

So, Mr. Eight-Pointer did NOT dodge a bullet, so to speak?! That would have pegged-out the Suck Meter... Our motto should be: "Thunking avoids Skunking"...

I'm going to try rolling up some "tightneck" 325s using 1680 right from the git-go...just to see what it'll do in moving "the wall" a little further away, if at all.

wildcatter wrote:Just to weigh in on all of this experimentation and to set some minds at ease.

When you straighten out the last third of the case to the mouth, you aren't going to experience any real problems, one might associate with this process, Vis-à-vis, the extraction, after firing, process.

The example I can site is the 30 Carbine round. The factory fodder is in fact loaded in this fashion, e.g., the last half (not the last third) of that case is in fact "Straight". The reloading dies for that case however, resize the case for a total taper over the entire length of the case.

My personal 45 Professional dies, to this day include, a 45 Colt, 45 ACP, and 45-70 dies.

What I'm trying to say is, ..Don't be spooked by none-traditional loading practices. Your real questions should be, am I getting enough Bullet Pull, so I can burn the powder properly, or I might not care if the powder burn is efficient or not, especially if I can use a better bullet for my intended Mission (This might just be the biggest concern..can I kill the target? Can I retain enough terminal-ballistics, to decide the issue when the bullet gets to the target, be it paper, steel, or flesh). After you decide theses issues, the only thing left and this is Paramount, do I have the correct Head-Space and does the cartridge pass my Thunk Test??

Heck, I even Thunk Test Bottle Necked Cartridges. If you're not doing it then start. Imagine, spending 20 Grand on a hunt, you want to use your Home-Rolls and when you get Afield, you discover your cartridges wont chamber..Oops! From my PH days, I always thunk and then chamber every round I intend to use, for I have seen ruined hunts, over this little matter..

..t

Not to change the subject, but I've searched on here and haven't found the actual description of the "Thunk test". How exactly is this done?
Jim

Jeepejeep wrote:Not to change the subject, but I've searched on here and haven't found the actual description of the "Thunk test". How exactly is this done?
Jim

Essentially pull the rear takedown pin. Remove the BCA. Tip the upper forward and drop a round into the chamber. It should drop in unimpeded and make a resounding "Thunk". Remove and repeat with all your rounds. In the case of my 450B, I check one or two rounds of a new loading run and if they weren't hosed, chances are good that the remaining rounds will not be hosed.

If however I am producing rounds for mission critical use, such as hunting or home defense, I test every one. In bottleneck calibers known to have collapse prone shoulders like my 300 Win Mag, cycling them in and out of your rifle is even more important. If I bought a box of reputable, manufactured ammo, I probably would not bother, but that's me. FWIW, I know the Deputies here at the Sheriff's Office do not cycle-check their commercial ammo right out of the box and they're certainly on a critical mission.

Hoot

Hoot,

Like both you & Tim said, I began using the Thunk Test, or Chambering test, on every round way back when I first began reloading. Not doing it on one trip to a remote camp in NW Colorado cost me a terrific buck. Had I not been fortunate enough to have brought a second box of ammo (loaded on a different day) along on that trip, it would have ruined my whole hunt. From that day to this, every round I load and every round I purchase gets the Thunk Test before going into my ammo cabinet. And yes, a few years back, I did find one box of Remington factory loads that needed a bit of resizing before they would chamber properly in my 7mm mag. Believe me, if I were a law enforcement officer, every round I carried on the job would have been thouroughly checked before I put my life on the line with it. Mistakes do happen. I can't tell you how many times on dove hunts I've found a factory shotgun shell that wouldn't chamber. I can laugh about those misses, but that same situation wouldn't be the least bit funny had I been looking down the barrel of some punk's 9mm at the time.

Now, back on subject: Were you able to get some of the "Tightneck" loads made up with those 275gr Barnes XTP's over the weekend? I've got a box of the Hornady RN 230gr FMJ's made-up that I hope to test out next weekend.

LlindeX wrote:Hoot, Now, back on subject: Were you able to get some of the "Tightneck" loads made up with those 275gr Barnes XTP's over the weekend? I've got a box of the Hornady RN 230gr FMJ's made-up that I hope to test out next weekend.

Not yet. I like your shim approach as much as the stem limiting approach. Lee uses a smooth stem and even with the collet cranked tight around it, you have to use some restraint when sizing so that you know when you've reached the stem contact point as opposed to just the resistance of resizing. Otherwise, you can drive the stem up and lose your index point. I marked the shaft with a sharpie line just in case, until I get more deft at it. Hopefully, I'll have some time this evening to pursue it after I walk the pooch and before bed time.

Hoot

Thanks, guys, I kinda thought that was it but wasn't sure. Now I have a bunch of ammo to "thunk"!

Jeepejeep wrote:Thanks, guys, I kinda thought that was it but wasn't sure. Now I have a bunch of ammo to "thunk"!

Yuppers, just "Thunk About It"..Wink..

..t