First shot ALWAYS high, then groups settle down...??

[FN in MT]

I have been working with a new Rem 700 SPS in .223 Rem. 1 in 8" , twenty inch heavy barrel. The scope is a Sightron III a 6-24X that has been accurate in the past. In Badger rings and picatinny rail +20 moa base.

From the start it has shot quite well but it will constantly place the first shot 1"- 1 1/2" above the eventual group. The four shot group after the initial shot average .5" .

So far I have about fifteen groups down range and ALL of them are the same; first shot high then the next four in a decent group.

Initially I thought the cheap plastic stock was possibly to blame as it would warp if left in the sun. So I replaced it with a new HS Precision stock similar to the one used on the Rem 700 XC's. It mounted up fine, locking lug area is tight and the bedding block seems to be contacting the edges of the action uniformly.

At the same time I replaced the HORRIBLE stock trigger with an 8 ounce, Timney unit.

I also noted the bolt lugs were not making uniform contact. So today I lapped the lugs and now both make full contact.

Fired two groups tonight at 100 yds, 60 gr Berger match slugs. Once again, first shot high, exactly 1" the next 4 into .380" and .520" .

I don't think its a scope, rings or bases issue. The stock also seems to have made an improvement.

The locking lugs I had hoped were THE issue, but it doesn't appear so. My groups did round out a bit and shrink but two groups are hardly a full test.

ANY ideas as to WHY my first shot is going HIGH? This is starting to drive me crazy.

FN in MT

 

[boltfluter]

Probably a stupid question but are you cleaning between groups? Action screws touching bedding block? Just thinking out loud.

Regards, Paul

www.boltfluting.com

 

[FN in MT]

Not stupid at all. After cleaning I fire a fouling shot. Always the same thing....first shot goes high.... The repeatability is rather amazing.

The action screws appear to be nicely centered and not touching the block.

Tomorrow I'm going to fire a shot, mark the tgt, let the gun cool 5 minutes or so....and fire the next, etc. See if they all group high.

FN in MT

 

[Dusty Stevens]

Sounds like a rest issue to me. Try to beat the back stock into the bag to settle it before the first shot. Rest issues are common to problems like you describe- recoil packing the bag. Is this the fouling shot you speak of or the second shot from a clean barrel? Br shooters always fire a few fouler shots to settle everything before a group

 

[FN in MT]

Regarding the "rest issue". I'm shooting off a Sinclair frt rest with a quality rabbit ear bag. I'm taking my time to be consistent using the same technique I use that yields small groups with other rifles. After a barrel cleaning I fire a fouling shot or two before shooting a group. I will typically set up, dry fire a few rds, then fire my first shot. Within 30-45 seconds fire the next, etc. Let the Oehler cycle out the results, make a few notes and within 2-3 minutes, fire the next group.

I'm not shooting this rifle for bench rest. The purpose of this rifle is for a local 400 yd steel shoot. Steel plates, scattered around the range, most small, from 100 to 400+ yds. As well as a coyote gun.

It will have an ATLAS bipod as soon as my 3" rail section arrives to mount the bipod. It will not see a frt rest again.

I have a pair of LR steel guns that shoot consistently small groups using an ATLAS bipod and a rear bag off of the ground or a mat, or a bench. I have certainly pulled shots but I identify those.

With this gun I feel I have done a good shot and the rd will go high. CONSISTENTLY. Then, using the same technique , shoot a decent group with the next four.

Can it be a barrel issue? meaning not properly stress relieved?

The barrel IS stock and having it out to lap the lugs yesterday, the barrel, lug, action interface appeared OK. Same for the action into the HS Precision stock. Trigger , or mag box not hitting the stock. Optics as well as the mounting system is of known quality, worked fine on another accurate rifle.

I'm going to shoot it today but wait several minutes between shots. See it that will give me a group with ALL shots consistently high.

 

[LHSmith]

In Score BR it is common to clean after the 2nd match (~ 24 rounds) or not until the day's agg is over ( ~50 rounds). It is pretty universal to fire a "fouler" at the beginning of each match ( 5 record matches + a warm-up match = an agg) since some rifles tend to shoot off POA on their first shot from a cool/ cold barrel. So, it isn't necessarily the need to "foul" the barrel as much as it is to bring the barrel to a more uniform temperature. Some barrels will shoot POA whether fouled or temperature "conditioned", but there are no guarantees it will in every conceivable load combination and atmospheric conditions. I consider it cheap insurance to "throw one away" ....it helps settle the bags and allows one to practice their gun handling habits at no peril ( the luxury of unlimited sighters within the allotted time limit).
Whether it's a bedding issue or inherent stress in the barrel, I take it as a given.... the "fix" for me is easy.....and my BR outfits cost several more times than yours.
When I speak "shooting to POA" - I am referring to an experienced shooter's learned ability to allow for conditions

 

[Mike Casselton]

Try shooting five groups without cleaning between each group.
Your barrel is settling down. If it shoots fine while warm and only throws the first shot you have no worries. If it walks, then you have an issue. What I'm saying is shoot the barrel under the conditions you plan on shooting in competition. Letting it cool between shots is a waste of time, powder, bullets, primers and range space. It doesn't show you anything

If your gun likes a lightly fouled barrel, then give it that. Stop fighting what you are being shown by the gun. You can think about it this way also, you won't have to clean it as much if it likes a fouled bore.
One last thing. If you are cleaning with harsh copper removing solvents, that could be leaving your bore dry. A dry bore = more bullet time in the barrel = higher impact on the target. It also causes more fouling. ..

 

[butchlambert]

I'll go with Dusty on this one.

 

[jpretle]

Frank, I thought all warning shots were supposed to be high.

 

[FN in MT]

Appreciate the replies.

The wind was wicked this past weekend, plus I was busy with other things......DID get the lugs lapped in, so now both are making uniform contact. That can't hurt. I'll shoot a few groups later today.

I will report my results.


jpretle,

Warning shots were always against Dept policy despite how much fun they could be at times. I have not been announcing myself BEFORE stroking the bang button. Which does allow for smaller groups and far better accuracy. But I appreciate the input.

 

[Mike Casselton]

Butch,
You and Dusty are probably correct on this one. OP didn't mention removing the rifle from the bags for cleaning, but did say that he cleaned between groups.
The bag thing has bitten me more than once in the first few shots.
Maybe the OP could try the bag thing with a clean rifle, then pull the gun out and sit another group with a dirty barrel to find the source of the problem.
As we all have done, changing more than one thing at a time will not show us the source of the problem

 

[Mike Casselton]

I hate auto-correct

*Shoot, not sit...

 

[Dusty Stevens]

Me and butch have the t-shirts being in BR as long as we have

 

[FN in MT]

After getting the lugs to mate up....the first shot issue seems to have resolved itself a bit. Still high, but now only 3/4" or so. I guess a rem 700 likes when BOTH lugs make contact. Not one hanging out in the air and the other making half contact.

Tried to shoot a few groups earlier but the mirage is so bad it's a waste of time.

Going to try to shoot a few groups late this aftn when the sun goes behind the mountains and things cool down.

 

[Dusty Stevens]

How much did you have to set the barrel back when the lugs came into full contact? Just wondering how far off your lugs were headspace-wise

 

[FN in MT]

Best I could determine I was .003" off.

Didn't need to set the barrel back.

 

[Dusty Stevens]

Be careful. On a saami chamber the difference between go and no go is only .003. Thats with forster gages. Nato is .010 for the 5.56x45. Just fyi

 

[Jason Boersma]

Have you tried different bullets? I had a BRX do that with the 108's changed bullets then the problem went away.

 

[butchlambert]

Not trying to be a wise A$$, but what in the World does lapping the lugs do? When you cock a Remington the upper lug unloads and doesn't touch the lug abuttment in the upper side of the receiver. When you cock your rifle the cocking piece raises the rear of the bolt unloading the upper lug. Only way to eliminate it is to bush and fit the OD of your bolt to fit a reamed bolt bore or buy a bolt that you can fit to the bolt bore. I never lap lugs as it accomplices nothing on a stock rifle other than increasing headspace.

 

[FN in MT]

Dusty,

With FL sized cases its fine, same for the factory rds I have. Possibly it was a bit long to start with?