Question for those smarter than me (everyone)

[Tcox]

I got back out today and tested in .2 increments. I may have found a winner despite the environmental conditions.





Swampratt, I attempted to get out to 200 with these but the wind was ridiculous between 150-275 yards. These were at 145~ yards. I did see some cratering, but I have been cratering on the well-below Max loads for some time with zero additional pressure signs.



Now here is the million dollar question: do I keep attempting to climb in charge weights until I see any more signs, or should I test .1 below and above this contestant then play with depth? As stated before, this is at approximately 2800fps with 143 grains of pill which is plenty.

 

[NikatKimber]

Are you doing these in true ladder test method? Fire (1) of each charge, then back through etc for groups? If so then that 42gr charge group would be an outstanding group.

 

[swampratt]

You see what NikatKimber stated.
You really find stuff out like that rather than shooting all 3 of the same load back to back to back.

Stick with 42 if you like it and see if you can make it happen on another trip to the range.

Shoot more than 3 of the load that pleases you.. take your time if you wish as to keep the barrel cool.

Now you may even shoot 15 or 20 of that same load .. keep track of which piece of brass shoots out of the group like a flier.
Then prep those 15-20 cases again and load them the same.. go shoot again and have the brass set aside that was a flier.. see if it is still a flier.. if it is then that should not be used again for shooting groups.. it can be used for a fouler shot.

Dang all the shooting

Wind sucks sometimes..
What i do see is that 41.2 through 41.8 shot the same height away from the black dot.. 41gr was lower towards the dot as was 42gr.

Did you have a chrony during this testing?

I loaded some .223 and reached a point where I was losing velocity .3gr more and averaged 50fps less. I was not at max for book reference either.
Funny how things work.

 

[Tcox]

Unfortunately I did not complete a formal ladder test. The extent of my latter test was start at a certain charge and move up in increments however each charge weight is at a separate target in 3 round groups much like the above photo. If I understand the concept properly, it would be best done at 200-300 yards. This will be possible, but not for a couple more weeks due to range availablity. Swampratt, it does appear that there is somewhat of a node between 41.2-41.8 maybe it would be best to play with depth and see if I could get something in those charges to tighten up? No chronograph, I need one but have not bought one

 

[swampratt]

If you can make that last load stay together during different range trips at 200 and 300 then run with it.
Now for those that missed it in the post those were shot at 145 yards.. excellent shooting.

Do it time after time and I would not mess with that load.

 

[Tcox]

Thanks guys, I appreciate it. I'm going to load again but I probably will not get back to the range till the weekend...

 

[Master Carper]

Looking at the photo of your badly cratered primer, you still have good radius around the edge, so it looks like you are safe as far as pressures are concerned...

I would recommend one of two things. First, drop you load a little bit and switch to Winchester WLR primers. They have a harder primer cup and should not crater as bad...

Second, if primers continue to crater, and look like the one you posted, have the bolt face bushed and a smaller diameter firing pin fit to it. Soomer or later, you are going to rupture a primer, and depending on the severity of it, it can be quite unpleasant to say the least...

 

[Tcox]

Thank you for the advice David. I'll switch from CCI bench rest to a different primer before I load for the weekend.

 

[swampratt]

I would load both types of primers if i was heading to the range.
One type may kill the groups.. or may change nothing

 

[Tcox]

Well, looks like a great evening. I'm going out to test my above load at 350yards! 5 rounds including cold bore coming up later!