Zak Smith

I surprised that the repsonses imply that so many people carry, well, really small guns for CCW. The three guns I rotate CCW are: a BHP (15+1), a HK P7 (8+1), and a Commander (8+1). None of these have a barrel under 4", all have a capacity of at least 9. -z

.40AET, Well, I scanned the Enos-sphere for 180gr MG & N320 loads a couple night ago and decided to try that one as a mild baseline. I wanted to rule out "too hot load" as a cause of the primer shearing. The load I've liked shooting the best so far is 5.3gr TG with the SR primer. I'll test a same-PF equivalent with N320 and see which one I prefer. But I've got to get this primer issue worked out first. -z

I tried this load: 180gr MG JHP, 5.1gr N320, 1.200", CCI #400 SR primer. v_avg = 923, sd = 19.6. Still saw the wierd primer effect. The 180gr MG JHP is only about 12 thou longer than the West Coast FP 180gr.

Here's the PRI tube. You can get it without the rails. It uses an Armalite "T" style barrel nut (included), but they have the option for an aluminum barrel nut to save some weight. -z

So the W.C. isn't going to cancel the match if it's "too wet"? Just making sure... -z

PRI makes a really nice carbon fiber tube, which is as light or lighter than the JP tube. -z

sh, No idea. My guess is stainless, but I haven't even removed it yet.

I just ran some quick ballistics for .270, assuming a 0.40 BC bullet launched at 3200fps. If zerod at 100 yards: _BC_ _MV_ 0 100 200 300 400 500 | YARDS 0.400 3200 > -1.46 -0.00 -2.50 -9.79 -22.57 -41.97 | > .270Win 130gr If about 3" high at 100 yards: _BC_ _MV_ 0 100 200 300 400 500 | YARDS 0.400 3200 > -1.43 3.26 3.98 -0.05 -9.61 -26.01 | > .270Win 130gr -z

.40SW, 5" SV Limited. Schuman bbl (NOT AET). TG is close in speed to N320, which tons of people use for Limited Major. I'll try backing down a bit and varying the OAL. Hopefully the batch I have will get me through RM3G. -z

I have a bunch of new reload data. H335 and RL10X seem to be the best choices for the 110gr VMAX. With some help from Marty wer Teeme (Teppu Jutsu / 458SOCOM inventor) on the internal ballistics modelling, it looks like these will hit 55000psi at about 2630fps (289PF). I haven't done a lot of work developing a 115gr load because the bullets I have are all pull down and no new ones are available. With 115's, we need 2783fps for Major. People with access to NDA and noncommercial powders are having more success with pushing the 115's to Major... but that's all I know.

I just tried seating a dummy to 1.270" (40 thou longer than my load). It drops in to and out of the barrel with ease. At 1.230", I should be very far from the rifling. -z

A dealer on AR15.com is taking orders for Beta-C mags to be delivered shortly after Sept 14th. $240 shipped. -z

I just started loading for my SV, and am still experimenting with combinations. I started off with 4.9gr Titegroup with a 180gr MG JHP, at 1.230". This chronod at just under Major, with a SD of about 35. Next, I pumped it up to 5.3gr TG. The average went up to about 935, with a SD of 25 or so. Switched to WSR primers. The average went to about 960fps with an SD of only 6 (!!) for a 15 shot string. I'm still getting primer flow into the firing pin recess, but this load doesn't feel very hot at all. It looks like the primer dimple is being "pushed out", and some of it shearing off. If this same PF (172) can be met with Clays safely, then using slower TG should be safe also. The max listed by Hodgdon in 10mm for a 180gr SIE JHC is 6.0gr TG with an OAL of 1.260". -z

Mickster, I wrote a detailed report last year: The High Road > Venues > Competition Shooting > Zak's RM3GM report with pictures further down that thread. -z

An Aimpoint M2 or TA11/TA31 ACOG with the front lens covered works identically to the Armson OEG. You're not looking "through" anything, but the dot appears on the target. For that matter, I bet the same idea would work with a Doctor or JPoint. -z

Combine JP's simplified & recalibrated TA01 reticle with BAC and that's it.

Rich had me do some testing on the first run of these about 6 weeks ago. I think the price is $7 for a packof 3. They were more reliable than the green followers for me. -z

Nice work finding that link!

[ link to larger image ] [ link to larger image ] Mike and I were picking up some breakfast at McD's before the "Sporting Rifle" match in Raton, and saw this leading the front page of the Sunday Edition. Not much "real" news in Pueblo, I guess ?! -z

TA11, donut reticle. The fiber-optic BAC feature makes target acquisition really fast, and the reticle is precise enough for any shot you'll find in 3Gun. It was murder on the long-range targets at SMM3G this year. Even though the BDC is calibrated for M193, it's within 6" at 400 yards shooting 75gr BH. -z

Just got back from the range. As I said, I gave the barrel a good cleaning with CR10, and cleaned out the action and b.c.a. With the Fed GMM 168gr, no pressure signs, no weird velocity variation. S.D. was about 15fps. Groups were about 2x as good (0.6 MOA) as I ever got with the BH, so I'm just going to switch to the Federal. I shot some new 175gr BH. Velocity variation was about the same as the Fed, but the accuracy was about 2x worse. Nothing strange with my 125gr handloads. I didn't shoot any more of the posssibly-faulty BH 168gr ammo. I'll give them a call tomorrow. -z

I was prepping my AR10 for a match coming up this weekend by chonoing and zeroing a new batch of 168gr Black Hills ammo I just picked up. I noticed that the velocity variation was pretty high - normally I get about 2620fps from a 168gr load, but I was getting readings as high as 2800+ fps. If everything else were normal and accuracy was good, I'd write this off to my chrono acting up. But after 20-30 rounds, I found several cases with blown primers in the pile of empties and stopped shooting. To my knowledge, this has never happened before with this rifle, shooting 175gr BH, 168gr BH, Fed GMM 168gr, or my 125gr BT handloads. I hadn't cleaned the barrel real well in about 500-600 rounds, but it didn't look like there was much copper fouling in there. I gave it a good cleaning with CR10, and I bought some new BH 175gr and FGMM 168gr to try this afternoon. Any ideas what's going on? -z

I was having this problem when I just got my .40 conversion set up. I sprayed the plunger down with Oneshot and the powder stopped sticking. -z

I was thinking about this question earlier this week in the context of rifle loads: Imagine a max load for 308 from a 24" barrel. Assume that going to a faster *or* a slower powder will yield a slower velocity (at 24"), when loaded to max pressure. The maximum pressure will happen when the bullet is within 6" - 10" of the breech. As long as the barrel is long enough to achieve the max pressure (in that 6-10" range -- call it 12" for margin), after which pressure trails off, all you will lose to a shorter barrel (e.g. in the 12-20" range) will be the incremental loss of velocity in that low-pressure regime. see http://www.shootingsoftware.com/pressure.htm for some graphs I claim that by going to a faster powder in a shorter barrel, all you can do is reduce blast while losing some velocity vs. the slower "max" load. By definition, the fast powder will peak and trail quicker. I downloaded the demo of an internal ballistics program QuickLoad http://www.neconos.com/details3.htm and played with a few things. Using a basis of a 300WM rifle with two powders "Quickload demo fast rifle" and "Quickload demo slow rifle" which are obfuscated so we'll buy the software obviously, I did the following experiment. Start with a 24" bbl, and chop it down by 5" every time, noting the max pressure and the MV: 73gr QL Demo Powder "slow rifle" Pmax Pmuz burn% MV 30" bbl 52507 9513 100 3118 25" bbl 52507 11909 99.96 2984 20" bbl 52507 15529 99.23 2805 15" bbl 52507 21356 96.53 2547 10" bbl 52507 31399 87.98 2127 5" bbl 52507 43656 55.48 1287 3" bbl 42961 35718 25.42 617 Note that the max pressure Pmax does not drop until you reduce the barrel length to under 5". Pmuz is the pressure when the bullet exits the muzzle. Note that the only change while reducing barrel length is Pmuz (goes up), burn efficiency (down), and MV (down). Then I substituted the fast rifle powder and found a load with the same max pressure (close): FAST rifle powder 20" bbl 52561 10255 100.0 2544 18" bbl 52561 11627 100.0 2477 For the comparison point 20", note that the Pmuz is much lower (about 30%) and the MV is about 300fps slower than the 20" with the slower powder. In summary, as long as the barrel is reasonably long -- specifically, long enough that the max pressure for max load for an indefinitely long barrel is still reached -- then the slower-powder max load will have more velocity in the shorter barrel than any other max pressure load with a faster powder. Relevant to this discussion is the observation that when the barrel length gets below the bullet distance at max pressure (in a longer barrel), the peak in-the-barrel pressure for a given load is decreased because by the time it would be peaking, it's already left the short barrel. Look at the 5" - 3" bbl data above.

I don't know about the spring strength. When using normal bolt carriers and gas blocks, I prefer the recoil impulse I get from a short carbine stock. I noticed this even more dramamtically in my AR10. -z