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David_S
February 17, 2008, 07:07 PM
We have two Model 70 Winchester featherweights, one in 243 and one in 7x57 both excellent for the type of hunting we do - chamois and deer in pretty steep country at around 4000-6000 ft altitude with typical ranges of 200 to 300 yards. We use the 243 mainly on chamois and the 7x57 mainly for deer.

Chamois are a small target (about the size of a goat) and unlike goats quite hard to knock down so accuracy is important. Has anyone had experience in accurizing these rifles?

With the 243 we have adjusted the trigger, pillar bedded the action and free floated the barrel. This has improved our groups at 100 yards to about 1.25 MOA which is OK but not that good. The Winchester manual for these rifles states that some fore end pressure is required for accuracy which seems to indicate that a free floating barrel is not recommended.

So our questions are:

1) What have others done to improve the accuracy of these rifles?
2) Is fully bedding the barrel worth a try?
3) Is fore end pressure desirable and how do you apply it? And how do you measure it or control it?

We have been using PMC 80 gr SP but have not found it very effective on chamois so have started reloading with Hornady 87 gr SP, which should improve our grouping but we still use the PMC as a control load for the "accurizing".

As an aside we have tried a bipod on the 243 with mixed results. From observation it appears that holding the rifle firmly causes the barrel to move down in the stock over the bipod which then exerts variable fore pressure causing erratic groups. When free-floating the barrel we just removed enough wood to allow a double thickness of paper to slide easily between the barrel and the stock but this may not be enough clearance when using a bipod. Any comments?

David

Wapiti
February 19, 2008, 10:59 AM
My 1961 M70 featherweight .243 is fully bedded. Can't say about "forearm pressure". I would think there is no pressure or even pressure, since that's the reason for bedding.
As for accuracy, mine likes the 100gr sierra best. Is your 1.25 MOA from a rest or from the shoulder. 1.25 with commercial ammunition is not all that bad, especially from the shoulder, if you incorporate the old "all fishermen are liars" strategy. Mine will shoot 1/2" groups at 100yd 1 1/2 at 250yd from a shooting rest with my most best reload. Usually it shoots 1" groups at100yd on the rest, and 1 1/2" from my shoulder.

mtnbkr
February 19, 2008, 11:12 AM
I've owned a 6.5x55 Featherweight for 5 years. To get mine shooting it's best (at least to the best of my abilities), I glass bedded the action and first inch of barrel, adjusted the trigger, added a pressure pad to the end of the forearm (barrel is fully floated from the pad back to the bedding 1" in front of receiver), and found a load it liked. The "pressure pad" is a 3/4" square piece of cork gasket material about 1/8" thick. It doesn't put a lot of pressure on the forend.

With all that, on a good day for me, I can achieve 3 shot groups with a cool barrel around .75" at 100yds. More often, I'm right at an inch or just under it, but I've shot a few .5" groups as well. This is off a rest with sand bags about halfway between the forend and magazine and another sandbag under the end of the stock. Via offhand shooting, I've always made the shot I needed, but I've never shot offhand for accuracy testing.

Prior to my "work", I was getting groups around 1.2". More than the accuracy improvement, the consistency has gone up. The groups don't wander around as the barrel heats up, they just open up a bit.

Chris

David_S
February 19, 2008, 05:37 PM
Thanks Wapiti and Mtnbkr for your replies. Very helpful.

As I suspected it seems the Model 70 Featherweight likes fore-end pressure or fully bedding. So the logical next step is to try Mtnbkr's method of some cork gasket material under the fore-end and if that does not help to try fully bedding.

BTW our 1.25 MOA is from a rest much as Mtnbkr describes. Anybody with thoughts on the bipod?

The 6.5x55 Featherweight would be a nice rifle - sort of between the 243 and 7x57. Great for our hunting conditions here. I have just purchased a second hand Sako M995 in 6.5x55 and am so far very pleased with it though it is a bit heavy to lug around the hills. Great action and trigger though.

David