Author Topic: Model 70 won't group  (Read 1515 times)

0 Members and 1 Guest are viewing this topic.

Offline jgrass5

  • Trade Count: (0)
  • Member
  • *
  • Posts: 36
Model 70 won't group
« on: November 29, 2004, 02:32:23 PM »
I have a 308 cal. model 70, 22" FWT. It has a fully bedded walnut stock, and  75 rounds fired through it. The best group it shoots is 3 to 4 inches at 100 yrds in a diagonal pattern. i've checked and retorqued the stock action screws, the scope mount and ring screws, no change.

i've tried several brands of ammo with different bullet weights, standard, premium and hand loads but no difference. I have cleaned the barrel very carefully after every 6 or 9 shots. I'm getting a little frustrated any ideas?

Thank you,
JGrass5

Offline Mikey

  • GBO Supporter
  • Moderators
  • Trade Count: (2)
  • Senior Member
  • *****
  • Posts: 8734
Model 70 won't group
« Reply #1 on: November 30, 2004, 03:21:40 AM »
jgrass:  first, I would unbed the barrel.  If you are fully bedded I feel the expansion generated by barrel heating in your fully bedded barrel channel may be causing your stringing.  Some folk might say it is the load you are using but that includes factory loads, so I would look to the bedding issue.  When I bed a rifled action I don't bed the barrel channel any further than the end of the chamber, and that seems to work for me.  

Also, you have a new rifle.  I would first see if removing some of that barrel channel bedding improves your groups.  If it does, then I would go the next step to firelap the barrel and that should close those groups right up.  HTH.  Mikey.

Offline jgrass5

  • Trade Count: (0)
  • Member
  • *
  • Posts: 36
Model 70 won't group
« Reply #2 on: December 01, 2004, 11:03:41 AM »
Thanks Mickey for the response. I have some time before i can get and fire the rifle again. I'll let you know how I make out

JGrass

Offline 270Handiman

  • GBO Supporter
  • Trade Count: (3)
  • Avid Poster
  • *****
  • Posts: 189
  • Gender: Male
Model 70 won't group
« Reply #3 on: December 06, 2004, 11:36:37 AM »
You might also check to see that the action screws are not causing the action  to torque(twist), because of being too tight.  I have heard of this causing problems before.  

Just a thought.

Offline JohnClif

  • Trade Count: (0)
  • Member
  • *
  • Posts: 98
Model 70 won't group
« Reply #4 on: April 05, 2005, 07:11:27 PM »
I've sold a couple hundred Model 70s over the past decade, and own a half-dozen of the Classics myself.

The biggest problem I've seen with the newer Model 70s is uneven or inconsistent forend pressure. The cure for this is to free-float the barrel.

I had a customer who bought a beautiful .264 Win Mag Classic Super Grade with an incredible crotch walnut factory stock. The rifle wouldn't shoot inside 2" and he was very upset. I took the rifle in for evaluation and shot it, and noticed that it shot much better groups when the sandbag support was under the action than when it was under the forend. The rifle stock was touching the barrel, and any forend pressure made it flex and touch the barrel even more. We opened the barrel channel up sufficiently to be able to slide a dollar bill up to the action, then cut a small groove in the barrel channel from the forend tip to within an inch of the recoil lug, and then filled that groove with Acraglas to stiffen the stock so it wouldn't flex. After that, the rifle would consistently shoot under 1 MOA with factory ammo regardless of where the forend was rested, and the customer was very happy.

I've seen this with several USRAC Model 70 hunting rifles, and so I wrote the factory about it, and suggested they open up their barrel channels slightly to ensure the barrel is free floated from the factory. USRAC believes that customers want a nice, tight stock-to-barrel fit and see it as a sign of quality. They don't realize that they are giving up the accuracy mantle to the Remington 700 unnecessarily (my Model 70s all shoot under 1 MOA as long as things are as they should be, i.e., free floated barrel). I guess it would take a little effort to modify the CNC program that routs the stock out and no one seems willing to do this.

Check your barrel to ensure it's free floating. Check it again while resting the very tip of the forend on something and supporting the rifle only via the forend tip and the very end of the buttstock (to ensure the maximum reasonable pressure is exerted on the forend to make it flex). If you can't easily slide a dollar bill up to the action and back, it's too tight.

Offline BruceP

  • Trade Count: (7)
  • A Real Regular
  • ****
  • Posts: 697
Model 70 won't group
« Reply #5 on: April 06, 2005, 07:35:56 AM »
Also pull your bolt out and run your little finger down into the bottom lug recess and see if you can feel the end of the front action screw. My M70 FW had a screw that was to long and it would rub on the recoil lug when I turned the bolt down. Cutting a couple of threads off the front action screw solved this and did make the gun group better.
BruceP
Lord, Please help me
Keep my small mind open
and my big mouth shut.

Offline moontroll

  • Trade Count: (0)
  • Avid Poster
  • **
  • Posts: 102
Model 70 won't group
« Reply #6 on: May 07, 2005, 06:49:40 AM »
my model 70 shoots the same hole at 100 yards,3 to 4 inch groups at 100 yards is alot and I would think something is wrong with the barrel. But Joncliff may have a point,but 3 to 4 inches seems more than a fitting.

Offline moontroll

  • Trade Count: (0)
  • Avid Poster
  • **
  • Posts: 102
Model 70 won't group
« Reply #7 on: May 07, 2005, 07:11:08 AM »
My model 70 has no sights,but if it were mine I would try to glue two bbs or no.#6(or so shot) to the barrel.One in front and one in back and shoot a group.If it didnt improve I would send it back.