I'm Stumped and need help

[BizBuilder]

I'm headed our west for an Elk hunt this fall. My Browning A-Bolt 270 wasn't going to be quite enough so I bought a new Sako Model 85 Finnlight stainless with a fluted barrel chambered for 7mm Rem Mag. The stock is Sako's composite stock. I put a Swarovski Z5 5-25x52 with the Ballistic Turrett on the gun for glass. I've run about 300 rounds through it to break it in. The last 100 rounds have been reloads (H1000 powder, 68.5 grns, using either 168grn Nosler Accutip LR's, or 168grn Berger classic hunter bullets).

I'm having trouble getting anything close to the kind of grouping that this set-up should provide. At a hundred yards I was getting 4 - 5 inch groups at best. The Berger's were grouping slightly better than the Nosler's (if 4" groups can be described as better). I had a gunsmith bed the barrel and the groups are now a bit tighter, but still about 3 inches at best. I decided to "take the shooter out of the equation" so I did two things. First, I shot the Browning 270 using factory rounds at the same range, same day, and was getting nice 1" 10 shot groups with clean crisp holes in the target. Second, I asked another shooter (who was shooting 1" groups at 200 yds with multiple rifles) to take a couple shots with the Sako. He put two shots inside an inch at 200 yds and then I put two shots inside an inch at 200. I waited a couple minutes and took three more shots at 200 and the grouping started traveling again out to 5 - 6 inches. It feels like I can get one or two good shots and then pattern starts traveling. I checked the scope rings and screws and all were tight. Another point of note is that I'm not getting good crisp target holes with the rounds I'm putting through the Sako.

I'm stuck on what to look at next. My sense is that there are four - five things that I could look at: something may be wrong with the scope; something may be amiss with the barrel; I could adjust the trigger pull; I could adjust the OAL on the loads; or maybe the shooter needs to be adjusted (Me).

What am I missing?

 

[Barrelnut]

Sounds like the scope could be slipping in the rings What rings are on the rifle and were they lapped?

Also might just be the barrel getting hot. Sako uses hammer forged barrels and they can "walk" the group when they heat up. A 7mag in a light barrel heats up quickly and would probably start walking after the 3rd shot. When you and the other shooter shot the 1" groups at 200 yards, was the barrel cool then?

Those are some loose groups though 4" to 5" is huge. I would think it's the scope slipping in the rings. Or... bad scope? Maybe try the scope off of the 270 and see what happens.

 

[johnnyk]

Biz,
I'm thinking you got two, may be three, issues you're trying to overcome. One is the sporter weight barrel. Usually, two shots and it's hotter than a shish-kabob skewer. Wait 3-4 minutes in between shots. I even put the rifle in my truck with the A/C on it to keep it cool. During hot weather I'll wait 30-45 minutes in between shots (I have a back yard range).
Trigger; what is it set at? 3lbs seems to be what everybody references as being the norm but I like mine even lighter. 2lbs is better to me.
Lastly, the barrel. I bought a Remington 700P in 7mmRemMag with the intentions of shooting the 168gn Berger through it. Apparently, the rifle had other plans. I tried and I tried to find an accurate load with that bullet and the best ran about an inch, but wouldn't repeat the next day. I tried a lot of different combos (powder/primers), seating depths and nothing came close enough. I finally said to heck with the Berger and when I ran the 150gn Ballistic Tip through it, it would print 1/4" groups. I gave the rifle to my son eventually.
Maybe try a lighter (150-160) bullet or something heavier (175-180). You never know till ya try. Good luck and keep us informed. JohnnyK.

 

[Bravo 4]

The 9.5 twist in your 7mag Sako should stabilize the 168 class bullets, but if they are not stable and leaving oblong holes (keyholing) on the target there is something wrong. It sounds like the bullets are stable, or they more than likely wouldn't be grouping so well for a couple/few shots at 200 yards and then sending fliers. Sounds like the groups are opening up due to the barrel heating. Now if the rounds were just not grouping or the zero keeps wandering I would suspect the scope first (or the rings/mounts slipping or such).
Sometimes rifles are just freaking picky. I was shooting an old sporterized 1903 Springfield 30-06 yesterday. This thing hasn't had a box of rounds put through it in 30 years so I don't know what it likes. I cleaned the barrel and proceeded to put an untold number of rounds with different powder, primer and seating depths for four different premium bullets of different weights. It was grouping 5-6" with one bullet, 3-4" with another and the best any of them did was 2". But not consistently. I had given up and was putting everything away and found half a box of cheap 180 grain Federal classics. I thought what could it hurt at this point, a three shot group printed well under an inch @ 100. I thought it was a fluke, so I make a quick scope adjustment and hit the small dot sticker I was using for an aiming point three times in a row.
Point is sometimes they just like what they like and not what you want. Keep trying, you never know.

 

[RockyMtnMT]

Check the mounting screws. Had this happen to me recently. Felt pretty stupid when I hadn't checked the simple things. It would shoot a couple good then way off. Fooled me for quite a while.

Steve

 

[BizBuilder]

Many thanks for all the feedback. From what I'm hearing it sounds like there are likely multiple issues at work that I need to work on: potential barrel over-heating; potential scope issues, trigger settings and bullet choice. Here's what I'm gonna try and then I'll report back what I'm finding.

Barrel - I suspect that the barrel is indeed "walking". I shot a group where five shots traveled a straight line up and to the right, with each shot about a half inch up and a half inch right of the prior shot, and then the next five shots did the same thing to the left with each successive shot a half inch up and a half inch to the left. It looked like a neat "V" on it's side. I'm going to try the range again but spend at least 3 - 4 minutes between shots to see how the barrel / shot grouping behaves.

My worry is that there may not be time to get a new barrel ordered and onto the gun before I head to Montana in November for the elk hunt.

Scope - I'm using Sako's OptiLock rings and mounts. I checked all the screws and everything looks tight. I'm not sure how scopes are "Lapped". The rings have a nylon/plastic ring on the inside of the scope rings that came with the OptiLock mount. That nylon/plastic ring is in place. I looked carefully at the scope and I'm not seeing any sign of travel - either vertically or horizontally. If taking my time between shots doesn't help then I'll try replacing the Swarovski with the scope off the 270. That scope is a Leupold 3X7 so it has good enough quality as a test scope.

Trigger - The trigger is currently set at the factory setting. I believe that's 4 lbs. I was going to wait until the gun was dialed in before I changed the trigger pull. At risk of changing too many things at once, I think I'll dial that back to 2.75 - 3 lbs. That's where I usually set triggers so my thinking is that it can't hurt.

Bullets - I wondered if excessive copper fouling might be inhibiting the lands ability to stabilize the bullets. I cleaned the barrel twice last night with copper remover as a precaution and I'm going to see how it shoots this next round. If this next round of shots shows the same bullet hole shapes then I'll start trying other bullets (162grn / 175grn / 150grn) and see what happens.

At the end of the day - this feels like a combination of scope and barrel problems. Does anyone have a good recommendation on a replacement Sako barrel?

 

[Laelkhunter]

Sorry not to have any answer to your problem, or a cure for the inaccuracy of your rifle, but I know this is not what you want to hear. You obviously have no confidence in your 7mm shooting the way it is. You DO have confidence in your .270 shooting the way it does. You can keep trying to make the 7MM shoot, but if all else fails, the .270 will be available for your Elk hunt. Use that, and with a Premium bullet (Nosler Partition, or Swift A-frame) you will not be undergunned with a .270. I have seen plenty .270's in the Elk camps that I have attended in the last 25 years. Of course I do see many more 7 mags, and 300 mags (Win & Wby), but plenty of successful hunts can be had with the .270. Confidence in your equipment is an important part of your hunt, and when you are looking through your scope at that Elk, you don't want to be thinking "Now will this gun put the bullet where it needs to go shooting a 4 inch group at 100 yards"? You will have enough pressure on you with Elk fever kicking in, and the excitement of the hunt. Take the gun that shoots the best, and the one you have the most confidence in.

 

[MBird]

Not to sound mean: but check the shooter. what i mean by this:

ensure you are mounting the Rifle the same way and in the same position

are you having to adjust to get the view in your scope,

Ring height? Eye relief? they moving the scope

if you are confident that all is good: they different bullets,

Side Note: your 270 put down elk with no problem, if you are not confident with your new 7mm, your 270 will work just fine

V/R
M.Bird

 

[Laelkhunter]

Side Note: your 270 put down elk with no problem, if you are not confident with your new 7mm, your 270 will work just fine

V/R
M.Bird[/QUOTE]


^ X2 lightbulb

 

[436]

I'm headed our west for an Elk hunt this fall. My Browning A-Bolt 270 wasn't going to be quite enough so I bought a new Sako Model 85 Finnlight stainless with a fluted barrel chambered for 7mm Rem Mag. The stock is Sako's composite stock. I put a Swarovski Z5 5-25x52 with the Ballistic Turrett on the gun for glass. I've run about 300 rounds through it to break it in. The last 100 rounds have been reloads (H1000 powder, 68.5 grns, using either 168grn Nosler Accutip LR's, or 168grn Berger classic hunter bullets).

I'm having trouble getting anything close to the kind of grouping that this set-up should provide. At a hundred yards I was getting 4 - 5 inch groups at best. The Berger's were grouping slightly better than the Nosler's (if 4" groups can be described as better). I had a gunsmith bed the barrel and the groups are now a bit tighter, but still about 3 inches at best. I decided to "take the shooter out of the equation" so I did two things. First, I shot the Browning 270 using factory rounds at the same range, same day, and was getting nice 1" 10 shot groups with clean crisp holes in the target. Second, I asked another shooter (who was shooting 1" groups at 200 yds with multiple rifles) to take a couple shots with the Sako. He put two shots inside an inch at 200 yds and then I put two shots inside an inch at 200. I waited a couple minutes and took three more shots at 200 and the grouping started traveling again out to 5 - 6 inches. It feels like I can get one or two good shots and then pattern starts traveling. I checked the scope rings and screws and all were tight. Another point of note is that I'm not getting good crisp target holes with the rounds I'm putting through the Sako.

I'm stuck on what to look at next. My sense is that there are four - five things that I could look at: something may be wrong with the scope; something may be amiss with the barrel; I could adjust the trigger pull; I could adjust the OAL on the loads; or maybe the shooter needs to be adjusted (Me).

What am I missing?

At this point who knows.. just kidding. Try some of the Norma bullets, I know, but give it a try anyway, drop the vel's a little not much, just a little'.., and seat them just off the land and groves. Trying to hard might be part of it.. just get them out the barrel at first.

FMJ 9,7 g/150 gr - #20670031
Oryx 10,1 g/156 gr - #20670041
Vulkan 11,0 g/170 gr - #20670061
Oryx 11,0 g/170 gr - #20670051

Good luck.
436

 

[RockZ]

I asked another shooter (who was shooting 1" groups at 200 yds with multiple rifles) to take a couple shots with the Sako. He put two shots inside an inch at 200 yds and then I put two shots inside an inch at 200. I waited a couple minutes and took three more shots at 200 and the grouping started traveling again out to 5 - 6 inches. It feels like I can get one or two good shots and then pattern starts traveling.

It looks like you have a good shooter for hunting.
2 shots inside an inch at 200 yds twice is very good.
Your rifle is not meant for high volume shooting. You only really need 1 or 2 well placed shots. .

I would make sure the carbon fouling is cleaned then clean the copper. You may have layers built up.
Also next time you go to the range shoot a fouler or two and let the barrel cool fully.
Then shoot a two shot group and see what you get. Let it fully cool again ,may take 30 mins ,and do the same.
Don't shoot more than a two shots at a time. Just keep the barrel cool. See how many good two shot groups with a cool barrel you can shoot.
Keep note how many fouling shots it takes for accuracy to settle in and how many for accuracy to decrease.
You want to establish a cold fouled barrel zero to take hunting.

 

[Wolf76]

are you only shooting h1000 powder at a specified weight? That could be your problem. Your load could be at the edge of a node and the heated barrel makes it worse.
What I'm trying to say is that my friend was ready to drag his 300 wsm behind the car on the way home from the range. Yes it shot like a shotgun at 200m. I had been loading 180 bullets with all the popular powders and nothing was showing any promise. It wasn't until the 5th powder that we found good accuracy < 1.75" at 200m. RL 15/17/22, Imr 4350 gave us squat. Imr 4831 was the ticket.
All that said, a 270 with a partition has been killing elk for a long time.

 

[BizBuilder]

Many thanks to everyone for the great insights. Ive tried just about all of the suggestions and ended up sending the gun back to Sako's repair/warranty service center to have them check it out. I hope to have the rifle back in about two weeks.

There were a number of suggestions regarding using the 270 instead for the upcoming elk hunt. As a confession - the 270 Browning A-bolt is a sweet gun. Unfortunately, it's a left handed set up for my wife. Bad news is that I'm right handed. Good news is that i have the best hunting buddy you could imagine! She's been known to out-shoot me...

I'll circle back to this forum with an update as soon as I get the rifle back!

 

[Catahoula]

Sounds like the same results I got with 2 different Sako rifles. A 22-250 & a 25-06. Never could get them to shoot. Found it to be a lot cheaper to go back to the Rem 700 than try to fix accuracy.
Thanks, Kirk