Thursday, May 03, 2012

Range Report #2: Improvements

. . . with a little coaching from the Professor:

.223 DRS 68gr. Hornady BTHP Match, $49.95/100

DRS Hornady BTHP Match 68gr

 

.223 Corbon Performance Match 59gr. HPBT, $13.95/20

Corbon Performance Match HPBT 69gr_hilite

 

5.56 Silver State Armory 63gr. Sierra Soft Point, $16.49/20

SSA Sierra Soft Point 63gr_hilite

Only four shots with this one.  I’ll explain in a minute.

.223 Black Hills 60gr. Soft Point, $32.95/50

Black Hills Soft Point 60gr_hilite

So, using the last two soft point bullets, the rifle jammed multiple times.  I don’t remember the technical terms for all the kinds of jams, but basically it seemed that the bold didn’t go all the way forward.  Once, the jam was so bad that the bolt wouldn’t go forward or back, and I spent five minutes trying to get the live round clear of the chamber.

I’m not sure how much the ammo is to blame, though, because about this time I became aware that my forward grip had been sliding down the well onto the magazine, which might cause feeding problems.  Professor?

Continuing . . .

.223 PMC Precision 75gr. BTHP Match, $16.95/20

PMC Precision BTHP 75gr

 

.223 Fiocchi 55gr. Pointed Soft Point, $9.95/20

Fiocchi Pointed Soft Point 55gr

 

Giving the Corbon another try:

Corbon Performance Match 69gr #2

I could feel myself getting a little tired and sloppy.  And ignore that little tear from the hole I cut out of the frame.  It’s from a .45 ACP that I made while waiting for a cease fire.  Not too bad at 50 yards . . . except that I was aiming at the target above it.

Note to self:  Next time you confront a bad guy hiding behind a shorter woman from 50 yards with nothing but a .45 . . . go to plan B.

 

Using the DRS with open sights:

DRS Hornady BTHP Match 68gr - Open Sights

 

Aww, skroo it:

Screw It

A bad day shooting still beat a good day working!

Notes:

1.  I concentrated on breath control, but also tried to relax into the stance.  It seems to be paying off, as all the groups tightened up.

2.  My impression is that ammo behavior is very specific.  Even when my five shot groups are tight, each different brand seems to pick its own quadrant, although I will need to test them again to see if the quadrants are consistent from one group to the next.  (Or rather, if I’m consistent from one group to the next.

3.  As last time, the PMC Precision is turning in the best performance.  I’m very happy with this ammo.  The Corbon seemed to have done well in the first round.  The Fiocchi Soft Point didn’t do nearly as well as the Fiocchi Match King did last time, but then it’s also lighter and a lot less expensive.

7 comments:

Professor Hale said...

You are keeping notes aren't you?

When will you be posting the graphs?

Forward grip sliding down onto the magazine? You mean your non-trigger hand was touching it? Shouldn't matter. Lots of people grip the magazine when shooting. Particularly if they use a bipod.

from your descriptions, it seems the missfeeds were very ammo dependent. I would drop that ammo from the lineup and see if that helps. That manufacturer may have sloppy processes that don't do well in your rifle.

Is your bolt lubed? With what?

Professor Hale said...

The next step is to pick an ammo that you think works best and practice with it exclusively. Keep more of that type around for SHTF situations. Too many gun owners still don't get the idea that not all ammo works the same.

As you practice and get your groups smaller, occasionally drop in another box of differnt brand to see if your improved ability matches up better with something new.

Dr. Φ said...

Prof Hale: Well, no, other than what I've blogged, I haven't been keeping notes and graphs.

Yes, my left hand was sliding onto the magazine. Glad to know it doesn't matter.

I'm using the Otis system, which advertises as both a cleaner and a lube. Which is good, because I haven't been lubing other than what remains on the parts after cleaning. Considering the number of problems I've been having, this may not be enough. (I have a post coming up about a kinda catestrophic jam with the Corbon.)

My favorite ammo is still the PMC Precision. It's a hollow-point, so appropriate for SHTF. Mainly I'm looking for a good-enough/cheap-enough ammo to use for plinking and high-volume drills.

Professor Hale said...

Ensure your bolt is well oiled in the bolt carrier. Oil on the other parts is less important except as a rust protectant. Don't put oit of any kind on the exterior of the barrel. When you shoot, it will warm up and the fumes get in your eyes.

I don't think the kind of oil you use is all that important so long as you use plenty of it.

Another thought: If you are using a carbine-length stock, you should also be using the carbine-length buffer, buffer spring and buffer tube. If they are mismatched, your bolt carrier will not return under proper push.

Also: If your front sight post/gas block is misaligned over the gas hole in the barrel, you will get insufficient gas pressure to operate the system.

These are common problems for people who build their own systems from parts. If your came from a reputable assembler, this is not very likely.

Dr. Φ said...

Thanks, I'll oil the bolt for next time.

I don't have the experience to evaluate the appropriateness of the buffer or the alignment of the gas block. What should I look for?

Professor Hale said...

Easiest way to check gas block alignment is to remove it. Use a paintmarker or small dab of nail polish on the block and the barrel to mark the alignment before you do, preferably on the side closest to the chamber. Then with the gas block off, see how far your mark is from the actual hole. If right on, then just reassemble it as before.

See my post here about gas tube alignment.

If that is out of alignment, it can lead to cycling problems.

Professor Hale said...

hey,
If you live in Virginia now, we can meet up somewhere and I can look at it for you.