First range trip with new 6BR build. Ho Hum results.

[MDM]

Well, I wasn't to impressed with my first testing session. Thought the 6BR was easy to load for? ;) I'm trying different loads of Varget with 450 primers. Tried some 107 SMKs and 87 Vmax, both jumped .020". I shot 4 shot groups. The best groups for the 107s was 29.4g measuring .71". The best with the 87vmax was .65". Some of the groups were plain crap. I think this gun must like lighter loads but I didn't see any pressure signs. My next batch for the 107s will go from 28.2g-29.2g. For the 87vmax, I'll go from 29.2 - 30g. My main goal is long range, so hopefully I can get the 107s to shoot .5" or better.

Here's the rundown...suggestions are welcome.

107 SMK and Varget.
29.4g = .71" Maybe there is a node right under this.
29.7g = 1.65"
30g = 1.34"
30.3g = 1.06" Maybe there is a node coming in a little bit higher?

87vmax and Varget.
30g = .65"
30.4g = 2.3"
30.8g = 3.2"

http://i66.photobucket.com/albums/h270/dm2596/groups1.jpg http://i66.photobucket.com/albums/h270/dm2596/groups2.jpg

[tammons]

What twist is your barrel ??
What scope and base etc ??

Maybe you just havn't hit a node yet.

My initial groups were not that great either until I switched over to 105 gr Scenars and 29 gr of H4895.
That was with CCI br primers.

I forget where I read it but that H4895 in that round shot tighter than varget.

I jammed the bullets about .015 and I guess I just got lucky and hit a node, because I immediately started shooting 3/4" groups at 300 yards
with no load development.

My setup was a SS short action w no work, pin removed from the bolt, midway shilen barrel, choate unbedded stock, nightforce scope, farrel base, burris extreme rings,
SSS recoil lug, SSS trigger.

[MDM]

Rifle stats...

28" McGowen
B&C Medalist stock
SSS trigger, rc lug
EGW 20moa base, Burris XTR rings, Weaver T24 w/ 1/8 dot

[82boy]

I would not hope for great groups shooting a VLD bullet, at under 200 yards. If your planing on shooting it long range, then you need to test it at long range, and not worry about 100 yard performance.

Most people report that that have best luck at 30 gr of Varget, and use of the 105 A-max. I found that I was getting pressure signs at 30gr with the 12 benchrest in 6br, but it shot good there. Try different seating depths, don't just say 20 off, and that is it. I found that with the 107SMK that a closer jump preformed better. 10 - 15 thou off.

Don't give up, and don't be afraid to experiment.

[MDM]

My plan was to find a power charge first, then experiment with seating depth. I didn't want to change too many variables at once.

[tammons]

What is your barrel twist ??

29 gr of H4895 is also a known accuracy load with the 105 amax.

No matter what or what weight of bullet I could not get Varget to shoot as tight as with H4895.
I think I went through about 4-5 range trips working varget loads before I switched.

I personally would start at the lands or just barely off and find a good load.

Edit, I looked back at my old targets and I did have some decent groups with varget, but no
1/4" 3 shot groups or anything. Still decent. If I remember right when I changed to that accuracy load my groups were cut in half.

[possum1]

I know nothing about the 6BR but hopefully in the near future I can build one. Before I changed powder I would experiment with seating depth.

[tammons]

29gr H4895, 105 gr Scenar at 300 yards.

http://i195.photobucket.com/albums/z300/tammons3/misc/6mmBR-4_resize.jpg

[MDM]

8 twist. Loaded up some more rounds to go to the range tonight or in the morning. .01 jump to .01 jam. It seems most are using varget or R -15 and some 4895. I couldn't find any amaxs or vld's locally. I'd like to get it to .5" at least. Gonna pick up some R-15 to try. I'll be going to the range every day until I get this thing figured out.

[tammons]

Have you been to this page??

http://www.6mmbr.com/6mmbr.html

Go to the bottom and look for accuracy loads.
I would start with those and work them a bit.

With varget I got tight 100 yd groups out of 80 gr bergers over 31 gr varget.

3.2" is a big freeking group for a 6mmBR.
Even with my worst groups I was never over about 1-1.25"

Is your barrel broken in ??

How are you shooting?

I had the best luck shooting free recoil.

[MDM]

Using a bipod and protector rear bag shooting free recoil. The barrel only has 39 rounds through it. However, after the 29 rounds fired today, no copper fouling and very minimal powder fouling, cleans super easy. Going to load up about 50 rounds and go at it again in the morning.

[tammons]

Try off of a regular front bench rest.

I would hazard a guess and say if you are shooting free recoil with a bipod, you are getting bipod bounce
and that might be some of the reason for the big groups.

[MDM]

I could be getting some bounce. I wanted to shoot it with the bipod because I will be shooting it prone in long range steel matches. I may just try sandbags tomorrow, or a firmer grip on the forearm with the bipod. I was worried that if I had sighted it in with sandbags and got good groups, that my groups may open up when I go to shooting prone with the bipod.

Anyway, I loaded nine rounds of each of the following charges - 29.6, 29.8, 30 and 30.2. Each charge will be tested at a .010 jump, a kiss, and a .010 jam. Hope I can find something.

[tammons]

If you are shooting off a bipod for a match I would sight it in that way, but you might want to do load development on a bag.

You have some huge groups for a 6mmBR and its obviously more than just the load itself.

I never had much luck shooting super tight target off a bipod. My groups on a bipod were usually about twice as big as my normal groups.
Couple of times I tried a towel under the bipod and that seemed to help a little. Typically I might be shooting 3/8" groups with my 223 on a front bag
and they would just generally spread out to 3/4" on a bipod. Still not much, but I was trying to dial in and shoot 3 shot groups through one hole.

That said I was never taught the proper way to shoot off a bipod and it took me a while to figure out why my groups were bigger with one.

I only use them for hunting now, so I am rarely on a really hard surface and dont really care if the group is 1/2" bigger in that scenario
unless I am shooting at crows.

If you are a member of snipershide, there is a video that shows how to preload a bipod to help prevent jump.

Edit: Also you need to make sure everything is free flaoted, barrel and tang, and make sure the action screws are not binding on the side of the hole.
I would bed the action too. Its not hard to do, just takes some time and patience.

Do you have a machined recoil lug on it ??

[mytwo60]

I shot my smallest 4 shot group with a bipod .068". I shoot in the .3s and .4s with a bipod all day long.

This is what I would do if I were you. With any initial loads always start right at the lands or .005 off. If this doesn't get you sub MOA at 100yds then something is seriously wrong with either your rig or your shooting. I mean you should be able to shoot sub MOA with most factory loads.

Assuming the basics are done (PROPERLY ->> bedding the action, scope mounting, chambered barrel) then I would say it's your shooting.

Even if your action wasn't bedded you should be getting tight 3 shot groups here and there and not the groups you're getting now.

[tammons]

I think its mostly the combination of shooting free recoil on a bipod, but maybe its something else.

http://www.6mmbr.com/TacticalFroggyA1.html

[allan1066]

I have a Savage 12F with Shilen 1 in 8 barrel and have been trying to sort loads with Varget and the 108 grain Berger bullet just out to the lands. I shoot 100yd 5 shot groups and seem to have bottomed out at about the .3's. Here is a series of targets with all things the same except powder weight ranging from 29.2 grains to 30.8 grains in .2 grain steps. These were shot with a choppy wind and probably accounts for the bit of latteral spread.

http://img.photobucket.com/albums/v639/allan1066/Shooting%20bits/th_groups3.jpg (http://smg.photobucket.com/albums/v639/allan1066/Shooting%20bits/?action=view&current=groups3.jpg)http://img.photobucket.com/albums/v639/allan1066/Shooting%20bits/th_groups2.jpg (http://smg.photobucket.com/albums/v639/allan1066/Shooting%20bits/?action=view&current=groups2.jpg)http://img.photobucket.com/albums/v639/allan1066/Shooting%20bits/th_groups1.jpg (http://smg.photobucket.com/albums/v639/allan1066/Shooting%20bits/?action=view&current=groups1.jpg)and here's the same load at 200ydshttp://img.photobucket.com/albums/v639/allan1066/th_200yds160509.jpg (http://smg.photobucket.com/albums/v639/allan1066/?action=view&current=200yds160509.jpg)

Keep at it - You'll love the 6BR when you get it sorted

1066

[McKinneyMike]

Using a bipod and protector rear bag shooting free recoil. The barrel only has 39 rounds through it. However, after the 29 rounds fired today, no copper fouling and very minimal powder fouling, cleans super easy. Going to load up about 50 rounds and go at it again in the morning.


There is an excellent video that shows proper technique for "loading" a bipod over on the Sniper's Hide forum. I can not find it right now, but will look again and try to post it. Well worth seeking it out.

I never knew that you need to put forward pressure on the bipod legs to help stop the "bipod jumping" that so often plagued my shooting and frustration. Works like a charm now!

[tammons]

Here it is on youtube.

http://www.youtube.com/watch?v=VjG1JZxiui0

[Dennis]

MDM, where did you get the target's from on your first post? I would very much be interested in getting the link to them.

Dennis