Ruger American, 308.
boyd stock, glass bedded recoil lug and rear tang.
bbl free floated except for i" fwd of recoil lug.
maybe 30 rds total fired thru it.
WW cases, federal match primers, 185 gr berger Jugernaut (sp) seated 2.806 COAL, 37.5 gr varget no crimp, shot off bench on bag at 125 yds
6 shots, 3 minutes, first shot in bullseye, next 5 in an almost perfect line straight down 2" c to c que paso?

#2...same as above but Lapua cases, 1 1/2" group, first shot in bullseye, rest in circle slightly to left. i know, USE LAPUA CASES. which is no problem, just more curious as to reason for vetrical stringing as above. thanks

depends on wat order the holes appear in the paper.
if one up one down/middle then down then up.
it's ammunition [or shooter] related.
if it's just up and up and up it's rifle.

it was bulleys eye, then down down down

In your case, you must have upward pressure at the fore end tip like Ruger does from the factory. Free floating doesn't always work with factory hammer forged barrels. Try it.
It ain't your ammo. Or you.

quote:

Originally posted by dpcd:
In your case, you must have upward pressure at the fore end tip like Ruger does from the factory. Free floating doesn't always work with factory hammer forged barrels. Try it.
It ain't your ammo. Or you.

using the hang a weight on the front sling attach while supporting the bbl to create downward pressure method or just a dab up front and reassemble and call it good?

That is one way but I use another way; put index card strips between the barrel and stock. Test fire it until you find how many it takes. Then leave them in place and don't glass bed it because you move on to something else. I actually use gasket paper because I have a lot of it, and it is thickness controlled, comes in various thicknesses, and I figure it is made to work under pressure.
That's what I do.

i used to do the same thing sorta in the early 80s using aluminum pull ring tabs minus the ring cut off and sized to bbl channel. been many moons ago though.

With lateral groups, two things can cause that, one is side pressure on the barrel in the barrel channal, but more often the side pressure is the result of the action pressure in the action itself...If these two don't work you can almost make book on a barrel problem as off center or crooked..

Target patterns are like the written word, they tell all as to grouping problems by shape.

my problem is up and down not sideways

If your velocity isn't consistent you can often see that especially if the variation is extreme.

What does it do with factory ammo?

no idea. started reloading the mid 60s. only factory ever shot is 12 and 20 ga and 22lr. even carried reloads on duty and when qualifying.
far as consistancy, am using a Prazipress, berger bullets, Harrells thrower, rcbs match dies and weighing every 3-5 rd on a 10-10 scale.

quote:

Originally posted by john c.:
no idea. started reloading the mid 60s. only factory ever shot is 12 and 20 ga and 22lr. even carried reloads on duty and when qualifying.
far as consistancy, am using a Prazipress, berger bullets, Harrells thrower, rcbs match dies and weighing every 3-5 rd on a 10-10 scale.

Consistency isn't the components you're using, although good components sure help, but rather how well you assemble the loads. Many things can vary your velocity and to name a few neck tension, how accurate the powder charges are, and whether the primer is seated correctly. I use a chrono when developing new loads to see what the ES's and SD's are. That help, but doesn't always mean it's the Holy Grail.

However, any potential variation in velocity will be random and will not make your bullets drop in an orderly fashion as you said.
It is the upward pressure on factory stocks that makes them work. Until you duplicate that, and rule it in or out, nothing else is germane.

Upward pressure on the barrel is your problem, that can be from the use of 3 point bedding and too much pressure in the tip of the stock, or it can also be cause by a warp in the action caused by poor bedding or undue pressue on the forward action screw also caused by bedding..The can be detected by use of shims under the tang and or under the forward action lug or first two inches of barrel..the use of lamp black is a good start as to the existing bedding. Its always an investigation, but up and down is the easy one, start with releaving the pressure in the forend..

Free floating is over played as a cure alland its not, its nothing more than one method that works sometimes, just like 3 point, and tight throughout.

Also keep inmind that changing a load can cause your problem, a hot load tends to shoot higher then a mild load and visa versa. I have also had better accuracy with warm to hot loads as a matter of fact..but depends on the gun make and model, I use strong actions.

If you can, check the velocity. I had one barrel which produced ascending velocity for the first six or seven shots and the faster shots hit lower at 100. At 300, the vertical was gone.
I would eliminate the bedding under the barrel as well. Regards, Bill

Ruger builds their rifles with upward pressure at the fore end tip. I suspect they don't do this for no reason. Everyone is ignoring that fact and is off on other tangents.

check the sling stud on the inside of stock mind was held with a nut on the inside of the stock and the nut back off,you could see the marks on the barrel. This caused my rifle to shoot all over the target put some locktite on the threads, tighten the nut and never had any more trouble

what is also being overlooked is that with lapua brass, its groups normally, strings with WW brass.
added bedding to forend tip, haven't had a chance to shoot it again yet.

quote:

Originally posted by john c.:
what is also being overlooked is that with lapua brass, its groups normally, strings with WW brass.
added bedding to forend tip, haven't had a chance to shoot it again yet.

Could be Lapua fits the chamber better, but more importantly has thicker case necks.

Hope you added upward pressure; not just bedding.
I must have missed the part about the Lapua brass.....

its in the OP