Mark II First Round Accuracy Issue

[Soonlobo]

My fairly new Mark II is a great rifle but for one issue.

About one half of each first round out of 2 of my four ten round magazines the round acts like a flyer. Usually hits at least one inch high. After this initial round the remaining rounds are fine and on target.

The mags seem to be seated correctly and feed fine. The bolt charges the round with no noticeable problem.

Any ideas?

Thanks in advance,

Soonlobo

[Old No7]

You didn't mention if you were loading a mag with the bolt open or closed...

If "open", try loading the mag with the bolt closed, to see if round #1 in that condition does what you say or groups with the other rounds. That way, all 10 rounds will enter the chamber under the same conditions, with pressure from the mag spring from below, and hitting the bolt at the top. It's possible the lips of those 2 mags are just different enough that they allow the round to bounce up or whatever and it enters the chamber differently than all other rounds that follow with a closed bolt.

Here's another thought, try those 2 mags only, with full rounds loaded. Load the 1st round like you always would -- but eject the unfired round instead. Then load and eject rounds 2 and 3. Using a magnifying glass, see if you spot any differences on the nose of the bullets between those rounds.

You can also using the magnifying glass to closely examine the feed lips of the trouble mags versus the others that work OK all the time.

"Something" is different, and a few controlled tests like this might help you find out what it is.

Tight groups.

Old No7

[Soonlobo]

Those are all great ideas. I've been loading with an open bolt so it makes good sense to change it up. Going out to the range in the morning and will try your suggestions.

Thanks!

[JCalhoun]

Will it do the same thing without using the mags?

[Soonlobo]

Didn't get to go out to the range the other day but I didn't notice a difference the other day when I loaded a couple of rounds by hand.

It doesn't make sense unless what Old No 7 says is correct and the different pressure is affecting the feed lips. Somehow the first rounds arent the same, I think it has to be what he says.

[Soonlobo]

Went to the range this morning to try out the Mark II as well as a couple of other things.

Loaded the rifle by hand, no accuracy issue, very good shots.

Loaded rifle with bolt closed, first shot accuracy problems with all four magazines.

Loaded rifle bolt open, first shot accuracy problems with all four magazines.

Talked to an older member of the gun club who also has a Mark II (with wood stock and blues barrel) and he said he has the same issue.

After the first round the problem does not occur and I get at least 1/2" groups at 50 yards.

Strange thing is the bullet goes either high or low but never a problem left or right.

Could it be a bolt problem?

[kingfish15]

Soonlobo---maybe it has nothing to do with the magazine. Try this--Fire one round, then refill mag and shoot all of them. Is the new 1st one still off? Or are they all now together. If everything is fine after getting that single round out of the way, it could just be your barrel likes to be heated up a little with that first round.
A lot of rifles will shoot the first round off a little from the rest. Just compensate manually for the first round. If it is shooting 1/4" high pretty consistently, hold 1/4" low for that first round and then shoot normally. Worth a try. Let me know if it works for you.