BluegrassDan
Member
Looking forward to seeing your results with the new barrel.
How many inch-pounds do you torque the action screws?
How many inch-pounds do you torque the action screws?
Here's my data from today.
Much hotter in Florida, 85 deg F. GNATS!!!!
As you can see, once again the first shot of high, this case by 1 inch.
The 3rd shot is the low one, I can't explain that.
There are nine shots total and as you can see, the rifle groups pretty well when it is not the 1st shot. The 2nd shot is somewhere in that glob of holes.
VELOCITIES: I dont' have the diffusers, so my chrony is very picky. It malfunctioned on most shots.
1st shot was 2914 fps
4th shot was 2902 fps (in the glob)
8th shot was 2992 (in the glob)
9th shot was 3023 (not sure where it went)
So yes, the first shot is somewhat slower. If that held up, I might could have some rounds with 1 extra grain of powder?
But the shilen barrel is on order now. 9" twist, bull barrel, 22" (short, thick), chrome-moly.
Oh -- one commenter wondered if my rifle "settles" in the rear bag after the first shot. I would consider that a possibilty -- except I do NOT see this with my 6PPC in the exact same front/rear rest.
Hi Docsleepy,
Reloading is a process. So whats my point. Well simply that we firstly need to ascertain if your reloads are consistent or if your Chrony hates you. Having said which the chances of each first shot being the flyer would be highly unlikely but as stated the spread was rather extreme. But the ammo must be the first check.
In my personal experiecnce faulty / lack of adequate bedding mostly presents as lateral groups and not vertical. Judging by the glob in the middle you can shoot, I am not one you believes in flyers (other than thoses induced by the shooter) you have a couple of "flyer" which probably were not you.
A couple of things to have a quick look at (not trying to teach you to suck eggs here);
-Is your barrel free of the stock? The old dollar note check.
-In a previous post I recommended that you check the firing pin assembly, your symptoms are classic of a broken / weak firing pin giving intermittent strikes. Have you checked your shot cases for varing firing pin strike depth?
- Do you clean your rifle after each range outing and then oil the barrel? If so do you make sure that all the oil is removed from the barrel before your first shot. An oily barrel can lead to 1st shot like yours.
- Do you store your rifle with the firing pin in tension or relaxed? If relaxed it may be that the for the first firing, the spring has rejuvenated a bit and then after the first operation relaxes back to its slightly weakened state.
-How many action screws to you have holding the barreled action in place?
Cheers
Andrew
Higher energy is recommended to assure ignition uniformity. Lets see if I can explain it. the industry pretty well figured out that .009" indent or less was a all no fire. Where .012" or deeper was a all fire. Frankford Arsenal found out in testing years ago that as the striker energy drops off vertical dispersion increased even though 100% ignition was being achieved.
I have a M1911 Swiss rifle that gives .022" indent. I had a La Corona 98 Mauser that gave .024" indent and I can't get a US made rifle to give me over .020 with factory spring.One is near on 80 years old and the other is 50 years old.
Another thing that has an effect is the amount of off center striker hits. Frankford studies also proved that up to a .020" offset there was no effect on ignition reliability but after .020" the misfire rate goes up. Which begs the question why are the gov't weapon specs allowing 1/2 diameter offset (of striker nose) to be fielded.
Try the following:
1. leave the copper in the bore but remove the propellant fouling quickly after firing.
2. Use synthetic grease on patch and make multiple passes until the patches come out same color as they went it. I use Grease Auto and Artillery GAA or Grease Aircraft Wide Temp Range WTR which are NATO spec greases.
3. The Swiss Army has used grease to clean bores over a hundred years now and I have never heard of a surplus Swiss rifle with a bad bore as received.
I normally run about 20 greased patches in bore ten passes. This will remove about 99.5% of the carbon (which is the enemy here). You want a tight fit so when the patch goes in bore it presses snugly on the walls of the barrel. I generally use a .27cal black nylon brush of a smaller caliber and wrap a 30 cal patch on that to give me a snug fit. When finished I leave grease in the bore.
A tight fitting patch will just leave a non visible trace of grease you cannot detect by visual examination. If you can see the grease left in bore your patch is not tight enough.
I believe your first shot will not be nearly as far out of the group.
Most importantly after your last shot remove quickly and get a greased patch downbore to remove the carbon. Carbon left to cool becomes hard and acts as an abrasive.