What causes two groups in one

[TradLife406]

I've had a couple rifles that sometimes will cluster five shots nicely then another five of the 10 shot group maybe a 1/4" under the other five. All the shots felt good.

Chatting with Avery a few months ago and he mentioned too much neck tension could cause this.

Anything else? Variations in powder charges?

Groups still very acceptable in size but it almost looks like two separate groups.

Just wondering if it's something that can be fixed on the loading bench.

 

[DANNY-L]

I've had this happen and I ended up bedding the stock and made sure barrel was free floated.

 

[TradLife406]

I've had this happen and I ended up bedding the stock and made sure barrel was free floated.

This gun was a Sig cross.
Other was a 6 arc gasser

Obviously the problem is they're not a tikka

 

[Scoutfan]

I have had this happen a few times. Most of the time it was the loose nut behind the trigger.- A little shift of pressure on the stock, different position in the shoulder, different cheek weld, sloppy trigger work.

 

[DANNY-L]

And front guard screw snug enough to keep in place, not white knuckled tight.

 

[SDHNTR]

Change in cheek pressure. Or change in bipod load.

 

[HuntHarder]

If it's 2 seperate groups after changing positions, I'd say it is likely a shooter error.

 

[Cold_Canadian]

This gun was a Sig cross.
Other was a 6 arc gasser

Obviously the problem is they're not a tikka

I have the same issue with my Sig Cross. Tried messing with different bipod loading and it seemed to help a little. I've also heard some stories of the cross having a loose barrel nut causing the issue as well.

 

[TradLife406]

Thanks guys!

 

[Lawnboi]

Parralax
Mirage
Your connection to the rifle
Diopter adjustment

I’d be looking at all that first.

Edit, saw it was a cross. That’s probably atleast part of your problem imo

 

[Q_Sertorius]

I've had a couple rifles that sometimes will cluster five shots nicely then another five of the 10 shot group maybe a 1/4" under the other five. All the shots felt good.

Chatting with Avery a few months ago and he mentioned too much neck tension could cause this.

Anything else? Variations in powder charges?

Groups still very acceptable in size but it almost looks like two separate groups.

Just wondering if it's something that can be fixed on the loading bench.

I would shoot another 10 shots into the same group. This doesn't sound like a real issue to me, certainly not one that can be fixed on the reloading bench. It's possible it is something that can be fixed by making corrections to the nut pulling the trigger.

 

[Castle Rock]

I've had a couple rifles that sometimes will cluster five shots nicely then another five of the 10 shot group maybe a 1/4" under the other five. All the shots felt good.

Chatting with Avery a few months ago and he mentioned too much neck tension could cause this.

Anything else? Variations in powder charges?

Groups still very acceptable in size but it almost looks like two separate groups.

Just wondering if it's something that can be fixed on the loading bench.

Oil between the action and stock will do that