Curios observation with reloads spraying

[WhelanLad]

So guys Ive noticed that with my Normal charge of Varget and a 140g bullet (woodleigh) that in my last Reloading session where I reloaded about 30 rounds, I 'set' the Lee thrower an just threw them in withiut checking each round (normal practise)


What I since found was erratic groups often at times 2 inch or so apart....
More commonly was the round flying Left and High approx 3 to 4 inches away from Bull....

I have pulled some of these rounds an the charges did Vary - at times up to half a grain...

Running them over Chrono was no major variences i dont believe but cannot be sure they were all new batch rounds.....

I then loaded an checked weight fir each 140gr Corlolt loads , which shot a Sub MOA group in a similiar POA / Zero with the other load...same charge..

I found this out when chronoing loads...some would be on the X..then the odd flyer High and Left....
I wasnt taking note of which rounds at first but then xlued on after I would 're zero' but find next shot/s were oppoaite the dial change..... wtf.

Is this sounding like a charge of Half grain out from a go to load?
Or more perhaps a component issue?

Is it common to have same weight projectiles Hit the same spot with same charge?
Is it common for the same weight projextiles to be at a sweet spot with the same powder charge?


I confirmed zero with 140core lokt... an shot the two batched woodleighs on same target.....

One High Left. -bad batch
2 good batch grouped with the new Corlokt load..


Hmmmm

 

[bearhunter]

This happens on occasion with the very odd batch of bullets.

I bought a bunch of Sierra bullets, 30cal, 165grn Game King that had been involved in an accident. The truck had gone over a concrete barrier and down into the Thompson River in BC.

The trailer had all sorts of commodities in it, including several dozen boxes of projectiles. Each bullet type and weight were packed in separate boxes that contained ten plastic wrapped bundles of five each by 100 count boxes.

I bought the whole lot at a dispersal auction, sight unseen.

I paid pennies on the dollar for these bullets so they were a great opportunity for me to stock up etc.

There was one problem, they had all been through some hard impacts and other agitation not normally encountered.

The trailer had floated down the river for a few miles, tumbling and rolling before it sank and stuck on the bottom.

It was in the river for at least a month before it was salvaged.

Surprisingly, the boxes of bullets stayed pretty much intact other than they had become very soft from the immersion. The bullets themselves looked fine, other than some discoloration from the water.

Almost all of those bullets shot as well as any that were normally encountered.

The ones that didn't shoot well were from the same lot and some of them had marks on them from the accident.

I thought it might be the damaged ones causing the problem but it didn't seem to make any difference on the bench.

I set those bullets aside and later just melted the cores out of them for casting and sold off the jackets for scrap.

I later read an article about bullets that had been subjected to impacts and how it caused issues with the jacket/core bonding.

In your particular case I doubt this is an issue.

Unless you have a lot of bullets it's hardly worth the money to invest in a Juenke gage, which will electronically measure the jacket thicknesses.

Sounds like you have a bad batch of extruded jackets with inconsistent thicknesses

How fast are you pushing these bullets, what is the twist rate of your bore and are your bullets maybe being ''over stabilized" for weight/length?? and not settling down to a sleeping mode before impacting your target???

Then with inconsistent jacket thickness you will also encounter "yaw" which is increased by the action of passing through air etc.

 

[propliner]

Are you getting the flier on the last shot out of a magazine?

 

[WhelanLad]

Are you getting the flier on the last shot out of a magazine?

gday, nah not so much, alot were single loaded- some minutes apart, lot of it was cold bore shooting it too . or letting it cool right off from a 2 shot string etc, but seems more one lot was different, to my knowledge they are all from the same Box iirc , these next batch will be same components but a closer inspection of the powder charge- weigh each one trickle in . etc.


i do have a 2013 model box of Woodleighs recently, so may experience some kind of variance there with those x50 ppsn's . so that is a interesting point about lot variences particularly a decade apart.

 

[WhelanLad]

This happens on occasion with the very odd batch of bullets.

I bought a bunch of Sierra bullets, 30cal, 165grn Game King that had been involved in an accident. The truck had gone over a concrete barrier and down into the Thompson River in BC.

The trailer had all sorts of commodities in it, including several dozen boxes of projectiles. Each bullet type and weight were packed in separate boxes that contained ten plastic wrapped bundles of five each by 100 count boxes.

I bought the whole lot at a dispersal auction, sight unseen.

I paid pennies on the dollar for these bullets so they were a great opportunity for me to stock up etc.

There was one problem, they had all been through some hard impacts and other agitation not normally encountered.

The trailer had floated down the river for a few miles, tumbling and rolling before it sank and stuck on the bottom.

It was in the river for at least a month before it was salvaged.

Surprisingly, the boxes of bullets stayed pretty much intact other than they had become very soft from the immersion. The bullets themselves looked fine, other than some discoloration from the water.

Almost all of those bullets shot as well as any that were normally encountered.

The ones that didn't shoot well were from the same lot and some of them had marks on them from the accident.

I thought it might be the damaged ones causing the problem but it didn't seem to make any difference on the bench.

I set those bullets aside and later just melted the cores out of them for casting and sold off the jackets for scrap.

I later read an article about bullets that had been subjected to impacts and how it caused issues with the jacket/core bonding.

In your particular case I doubt this is an issue.

Unless you have a lot of bullets it's hardly worth the money to invest in a Juenke gage, which will electronically measure the jacket thicknesses.

Sounds like you have a bad batch of extruded jackets with inconsistent thicknesses

How fast are you pushing these bullets, what is the twist rate of your bore and are your bullets maybe being ''over stabilized" for weight/length?? and not settling down to a sleeping mode before impacting your target???

Then with inconsistent jacket thickness you will also encounter "yaw" which is increased by the action of passing through air etc.

yeah thats interesting.


its a kimber montana all factory spec. usin a 140gr in 7mm08 , shouldnt be a stabilaztion issue-
bach of bullets maaaybe but iirc from same box. will note this on next batch i load for it.

 

[Jon87]

1/2 grain is quite a bit of variation. I wouldn’t expect that to shift your POI so much at what I’m assuming is 100 y/m though. Have you cleaned your barrel recently? I had some copper buildup in a tikka barrel once that caused similar issues to what you’re describing. A couple rounds of wipeout and it went away and never returned.

 

[bearhunter]

yeah thats interesting.


its a kimber montana all factory spec. usin a 140gr in 7mm08 , shouldnt be a stabilaztion issue-
bach of bullets maaaybe but iirc from same box. will note this on next batch i load for it.

I recently had a similar issue with neat 98 Mauser, chambered for the 303Brit.

Turned out the powder I was using, IMR4320 had started to deteriorate. Had to throw out several cans.

I now have about a pound and a half of IMR4320 left and they don't make it anymore.

 

[Mystic Precision]

weigh each charge and see if the accuracy/consistency returns... then you have your answer.

extruded powders do not flow well through powder measures...

Jerry

 

[WhelanLad]

weigh each charge and see if the accuracy/consistency returns... then you have your answer.

extruded powders do not flow well through powder measures...

Jerry

im hearing you on this one, thats where my thoughts are at almost 100% , ill touch base once ive gotten back out after i load some new ones!


the exact weighed corelokts shot moa or maybe tighter 3 shots, feel like i re learnt not to throw extruded powder an expect minimal variation... ive not pulled them an weighed them all but seen enough varience to think along this line too.