Tracking/recoil Question

[noload]

I shoot F-class open, 300-1000yds. I've noticed Tracking discrepencies in my set up on a SEB NEO2 and a Doggone good rear bag. Looking thru the scope, aligining the cross hairs on the X , let say at 300yds and then sliding the gun about 1.5" rearwards my cross hairs move off the X and low left about 1.5". But when I slide it back to battery it is aligned again with the X. I seem to struggle to get it to slide straight back and forth and stay close to the X thru the whole cycle. . I get it the best I can by cycling it and taping the rear bag. I score rather well as it is...... My questions are;
1. Do the rest of you guys have this condition ...(tracking rearward walks off center)?
2. Will walking off center during recoil effect my POI ?.. Will all shots be the same since the tracking is the same?
3. Why do some benchrest shooters use tappered butt stocks, other use parallel to bore butt stocks?
This may be a question for a BR shooter.
Depending what your answers are.. I may build a new stock?
May be nobodies gun tracks back perfectly????? Thanks, Pat Lundy

 

[Alex Wheeler]

Your stock is not straight. Fix that and the gun will track.
Short range Br rules require the stock to have drop in the rear, long range Br does not have that rule.

 

[noload]

I did not know that was a BR rule. (Tappered butt stock). I learned something. I may have to do some stock work.

 

[22BRGUY]

Not sure if this will help but I always try hard to make sure the rest in front and the bag in the rear are in straight alignment with the target before I set the rifle in them. I use a straight rod first to align everything. After the rifle is in place I do what you did to make sure things are tracking in a straight line. I know the muzzle will lift with recoil but that doesn't bother me if it remains straight. JMHO

 

[dmoran]

What stock?
How much taper in the finished stocked rifle?

For LR Benchrest I like no taper.... and has to be built into the rifle.
By starting with a parallel blank and machining it to true parallel, and bedding the action/barrel parallel to the stock.
Seen what I consider faults to the blank stocks and bedding methods, that IMO can't be taken for granted.
Rest and bag forming as well as Setup are key elements as well.....

My 2-cents
Donovan

 

[NateHaler]

Pat, I understand how we can all obsess about details and why things happen, but it seems to me that if your tracking consistently puts you on the X when you're in the firing position (i.e. at the end of your forward motion), then you don't have a problem. Who cares where the rifle goes when it's moving backwards under recoil, as long as it doesn't fall out of the bag (!) and goes forward to where you want it?

To fix this situation, I think the other poster is correct; you'll need a stock and/or rest setup that will effectively keep everything on the same plane (up/down and left/right) at time of shot and after recoil. But isn't the main idea, by far, to shoot little bitty groups in the 10/X ring? And if you're doing that, then who cares about tracking like a trolley on a very short railway?

But don't mind me; when I shoot F-Class, it's F-TR, and I use a Harris bipod and a rear bag (on occasion) that has rice in it from 1999. My survival rations I guess, or in case the match lunch is really, really putrid.

 

[22BRGUY]

Pat, I understand how we can all obsess about details and why things happen, but it seems to me that if your tracking consistently puts you on the X when you're in the firing position (i.e. at the end of your forward motion), then you don't have a problem. Who cares where the rifle goes when it's moving backwards under recoil, as long as it doesn't fall out of the bag (!) and goes forward to where you want it?

To fix this situation, I think the other poster is correct; you'll need a stock and/or rest setup that will effectively keep everything on the same plane (up/down and left/right) at time of shot and after recoil. But isn't the main idea, by far, to shoot little bitty groups in the 10/X ring? And if you're doing that, then who cares about tracking like a trolley on a very short railway?

But don't mind me; when I shoot F-Class, it's F-TR, and I use a Harris bipod and a rear bag (on occasion) that has rice in it from 1999. My survival rations I guess, or in case the match lunch is really, really putrid.

Gotta agree...In the end beauty is as beauty does.

 

[Old Navy]

Informative topic. Thanks. Frank

 

[Alex Wheeler]

I agree, for f-class its not that important, you have time to make small adjustments to poa between shots. If your coming back to the x thats all that matters in your game. I had a really crooked st-1000 (big surprise huh?) I spent some time getting it straight, it did not shoot smaller groups, but it did shoot those groups alot faster.

 

[noload]

I'm thinging that if a stock tracks perfectly straight back, the POI's will be closer to each other. My condition may also produce the same POI, since it probably tracks rearward the same every time it's fired. But not necessarily so if minor changes between each shot have to be made. I guess I'm looking for a Bench rest setup for my F-Open rig.... The stock in question started out as the original S&H aluminum core with V block that came with the Savage LRPV 6br. I machined a aluminum 3" wide front pc and aluminum rear piece the would bolt under the rear of the tappered stock to make it parallel to the barrel. Bolt pieces were drilled and tapped to the aluminum core of the stock and bedding material was used where they met the stock. I did this so the stock could be used for Open or converted back to original for F/tr. I leveled the barreled stock off the barrel, used a starrett precision level also to place and bed both added alum. pcs. . This has been used like this for 5 yrs and has worked well, I am inclined to think the rear pc may be off a bit, causing the windage condition I see during prep period tracking.
Am I correct in thinking that BR guys can shoot a string thru their gun with out looking through the scope once set up correctly? By the way I do set up my front and rear bag very carefully initially, I do understand the theory of alignment. I have shot my buddies setup on occasion, McMillan Tolley MBR, stock, If I recall that has a slight tapper on the butt stock and can you expect a verticle change when clycling back and forth. FWIT it shoots well. ZFAST I will straighten that stock ....I got the same feeling it might not shoot any better. That stock did shoot 150/15x at 300 yds. But think it can get better. Pat

 

[NateHaler]

Am I correct in thinking that BR guys can shoot a string thru their gun with out looking through the scope once set up correctly?

Maybe with a rail gun. But when I watched Bill Shehane shooting a longrange BR match, using his heavy gun setup, even though he fired his groups real quick, he was peeking through his scope each time.

Short of a railgun, it would take nerve and utmost faith in one's gear to not look through the scope again once set up correctly, as you put it. There should be a separate class for it: Cold Turkey.

 

[LHSmith]

Am I correct in thinking that BR guys can shoot a string thru their gun with out looking through the scope once set up correctly?

Perhaps your thinking of an unlimited (rail) gun? But in a bag gun, no. On occasion a bag gun shooter might shoot "heads up" ( firing without looking through the scope in an effort to concentrate more on the flags), but he must always bring the rifle back to battery and tweak the POA through the scope first.
I am a short range bench shooter, but I am not sure a Doggone bag is constructed well enough to offer the consistency needed. Finding the right rear bag (ear size, ear spacing, and filling it the proper amount and type of sand is an art in itself.

 

[noload]

I am a short range bench shooter, but I am not sure a Doggone bag is constructed well enough to offer the consistency needed. Finding the right rear bag (ear size, ear spacing, and filling it the proper amount and type of sand is an art in itself.

I don't know if you have used this type of bag or not , I really like the way it grips the sides of the butt stock. I've been using a Doggone bag for about 3yrs now. With the gun /stock set up I have, that bag shot better than other top notch bags out there. I find it craddles the rear stock and keeps wobble out of it. I use stock tape and friction free cloth where my stock rides. If I change my stock I may find another type of rear bag may work better, but not on the stock I'm using now. Proof on paper got me to this point. Pat