Author Topic: 204 & 35 gr berger report the good the bad and the ugly (Read 562 times)

aulrich · « **on:** August 14, 2005, 02:07:53 PM »

The good

The berger heads shoot quite well just over the half inch mark using 27.5, 27.8 and 28 of H4895. I'll be using 28 for this years coyote load since when I am going hunting it will be anywhere from 20 - 40c colder. Coyotes beware.

The bad

The groups should have been almost half of that. I am getting vertical stringing, not really bad but definitely there. I suspect that lock up is the culprit because I am getting a significant percentage of openings when I fire. And it seems to get worst as the gun warms up (on the half inch groups the flyer was when it opened without the flier the magic .25 could have been broken).

The ugly

Using blc(2) @ about 1.3 grains below max I blew a primer. needless to say I was not impressed. I am not sure what is up with the blc2 loads. every time I have tried them with especially the lighter bullets I got pressure problems. With the 40 grain heads I was able to get to within .5 grains of max. it's not like the loads are not accurate it's just that I am way off max.

So far this gun is basically out of the box (i did do a good cleaning and a barrel lap too. But I am going to have to get this lock up issue dealt with.

quickdtoo · « **Reply #1 on:** August 14, 2005, 02:25:00 PM »

Hone the latch shelf on the barrel with a fine arkansas or similar stone, it should improve the lock up. You can check the amount of engagement by cleaning the latch shelf real good, then smoke it and install the barrel and lock it up, check the engagement mark in the smoke after removing the barrel, it should be about 1/8". I use a fine hone from my Lansky knife sharpening kit, they have nice sharp edges perfect for Handi work!!

aulrich · « **Reply #2 on:** August 15, 2005, 05:26:51 AM »

When you are stoning the shelf do you do x strokes and fit then repeat if needed I am thinking that x would be 5- 10 strokes? I am figuring a small hard pocket stone would work (My lansky kit go lost in the last move). I have generally hav stopped using stones for sharpening, I do most of my sharpening with abrasivepaper glued to glass plates. I started using this with my woodworking tools and just use that for my knives now. But it won't work for this application so I'll be picking up a stone.

quickdtoo · « **Reply #3 on:** August 15, 2005, 05:34:15 AM »

Yup, just hone a bit, clean, smoke and check the fit again until you get good engagement. It doesn't take too much.

Fred M · « **Reply #4 on:** August 15, 2005, 11:22:52 AM »

Quick.

The problem I see with the flat stoning, and I have made reference to this several times, is that the latch is making contact only at the tangent of the latch radius and the latch travels in an arc. The tangent support will eventually dig into the seat and loosen things up again That is because the latch is very hard and the seat soft as s---.

Lowering the latch seat on the same flat is not stopping the latch from sliding back. The latch seat has to have the same radius as the latch to provide a good friction fit supported by a strong latch spring.

quickdtoo · « **Reply #5 on:** August 15, 2005, 11:28:49 AM »

Yeabut, it works for our purposes without re-engineering the latch mechanism which is beyond the capabilites of most every one of us. It's not perfect, but it works. :wink:

Fred M · « **Reply #6 on:** August 15, 2005, 12:10:09 PM »

Quick.

I am not talking about re-engineering but providing a concave latch seat.

If that is beyond capability then by all means do it your way. I did not think my writing was that bad to confuse a good fitting latch seat with re-enineering. :cry:

quickdtoo · « **Reply #7 on:** August 15, 2005, 02:12:04 PM »

Sorry Fred, didn't mean to step on your toes, but I've honed many latch shelves and it hasn't hurt accuracy one bit and I've never had one pop open on me, even with 2400fps 300gr 45-70 loads. :wink: I like to see 1/8" of latch engagement, when I see less than that, it's not up to factory standards, I'm sure. I'm also sure that's why a lot of new barrels pop open, they haven't lapped themselves in yet, I just help it along a bit... :grin: I also think your heavy duty springs help a lot!!!! I put one in the .338-06, 405 Winchester and 35 Whelen, and have one left for?

aulrich · « **Reply #8 on:** August 15, 2005, 06:35:46 PM »

Well I go myself a pocket hone and honed the self today after work. The one thing I did notice right of was that the mark in the soot was not even. Well it is even now but I am not a full 1/8" in I have to admit to not wanting to mess up, I can always hone a little more. I have to close the action smartly to get really reliable lock-up but there is definite improvment. I'll be testing it again in a couple of weeks.