Help find thread, 3rd shot falls out of group

[nwmnbowhunter]

There was a recent thread about 3rd shot falls out of group.

I can't find it... if someone could link it for me I'd appreciate it.

Thanks
John

 

[nwmnbowhunter]

Here's the problem I'm having. First two are good. 3rd falls out. Es under 10. 4 groups in a row. Seating depth shorter and longer both open up.

 

[C.E.Smith043]

What caliber, and rifle details please.
Also what distance and conditions

 

[Big Mc]

Here's the problem I'm having. First two are good. 3rd falls out. Es under 10. 4 groups in a row. Seating depth shorter and longer both open up.

View attachment 1494700

Get a friend too shoot it. If his stay in the group . It is your technique, or setup problem. Tommy Mc

 

[Murray Brook]

Could be a bedding problem. If you feel the bedding is good then I would try a primer change after trying what @Big Mc posted

 

[tmwinds]

Shoot three five shot groups and see what happens.

 

[LVLAaron]

Looks good to me

 

[nwmnbowhunter]

What caliber, and rifle details please.
Also what distance and conditions

7prc
175 berger elite hunters.
Retumbo
fed 215m primers
8 twist
Built by top shelf builder

Actually have two 7 prcs with different reamers that are doing similar things.

4831sc was terrible

8133 was terrible [tried it because i have a bunch to use]

Retumbo gave best es and best group potential.

Going to fire another 50 down the pipe and get it well broken in and then have firformed brass

 

[lawman29]

6.5x47 throwing third shot

I know this sounds stupid but I keep chasing my tail and cannot figure it out . 6.5x47 benchmark barrel , trued 700 130 eldm jumped .020 450 cci Varget .002 shoulder bump 200 yds Shot off a bench with a rest front and rear No wind . Shot this today . ( load development ) Puts 2 in there good...

forum.accurateshooter.com

 

[drover]

OP - Are you only shooting 3 shot groups or are you shooting 5 shot groups?
The reason for asking is that if you are shooting 5 shot groups where do # 4 and 5 go? Do they stay out of the group made by the first two shots or do they go back into the group.

If you are shooting only 3 shot groups then I suspect that the recoil from the first two shots are causing you to anticipate the recoil from the third shot and you are tightening up or holding the rifle differently. The fact that you mentioned having two 7PRC rifles doing the same thing is taking me down the road of thinking.

drover

 

[6MMsteve]

Here's the problem I'm having. First two are good. 3rd falls out. Es under 10. 4 groups in a row. Seating depth shorter and longer both open up.

View attachment 1494700

did you see those low shots hit when u pulled the trigger, if not you flinched, maybe I flinch 10x sometimes before I shoot just me Ol Shaky

 

[nwmnbowhunter]

did you see those low shots hit when u pulled the trigger, if not you flinched, maybe I flinch 10x sometimes before I shoot just me Ol Shaky

Trust creedmoor didn't drop any shots and i that's why i shot 4 groups to prove it wasn't me

 

[Coyotefurharvester]

You are close to a compressed charge weight( with Retumbo). But still have room on a load chart move up 0.2 gr see if that flyer closes more, vertical calls for slight powder increase. Unless you have already found your max.

 

[Sniperhandle]

Here's the problem I'm having. First two are good. 3rd falls out. Es under 10. 4 groups in a row. Seating depth shorter and longer both open up.

View attachment 1494700

Speedy had a post that said spitting a shot can sometimes be remedied by dropping or increasing powder charge by a 1/2 grain. I am not sure if it was on this forum or somewhere else I saw his post or article about what he refers to as spitting shots. It's worth a try.

But vertical stringing can be caused by bedding for sure. It's also best to shoot 5 shot groups not 3 shot groups.

 

[David Christian]

I think I just read this is virgin brass? Is that correct? How many rounds on the barrel? What load work up have you done already? What distance are you shooting for these tests? Have your tried different bullets or different primers? I think we need more details to be helpful.

 

[nwmnbowhunter]

200 yards
Virgin brass
3 different powders
3 different bullets

I'm working thru my process and will get all fire formed brass and get over 100 rounds down both barrels.

I've had lots of custom rifles and just never seen one, let alone two, do this so consistently.

I did have this happen earlier this year and my brake had popped loose.

There have been a few ideas here that I'll try... primer change being number one.

 

[Forum Boss]

When I see that sort of thing, I recommend:

1. Let somebody else shoot the gun. We saw one rifle that did this with owner, but shooter #2 got a horizontal line, and shooter #3 got a nice round group. The owner had inconsistent hand and head pressure on the stock.

2. Check the action bolt connections and torque.

3. Try another scope.

4. As others have stated, check barrel to action tightness.

5. Check for damage to muzzle crown.

 

[lawman29]

Another way is to shoot your groups round robin and see what happens...