HELP - Troubles with my M71

71fan · Post by **71fan** » Sat Sep 29, 2007 12:36 am

Two weeks until I leave for Wyoming on an elk hunt, and the M71 is acting up. I haven't shot it since my pig hunt in April, when it was consitstently grouping at 2-1/2 inches with my reloads.

At the range today, the first group at 100 yards is about 11 inches vertical stringing. NThe next group tightened up to 8" vertical. The horizontal spread is about 2 inches. Obviously this is totally unexpected, and quite poor performance.

I moved to 50 yards, where I can usually get 1 inch with this load, and got 3 to 4 inches for 3 4-shot groups.

It's the same batch of reloads I used in the spring when everything grouped fine. I'm shooting 66.0 gr H4831, Hornady 200, and WLR primers. The sights are a Sheard bead and a Lyman 66.

Everything is tight on the gun - forearm, sights, etc.

I was shooting my 1886 and Marlin 39A just fine, so operator error is not a factor.

WHAT GIVES??? What could have changed to cause such an extreme loss in accuracy?

I leave in less than two weeks. I'm freaking out a bit.

I have plenty of Silvertips, and about 80 rounds of Buffalo bore 250s, so I guess I'll try again and see if I can get get these to group.

Any insight, opinions, suggestions would be greatly appreciated.

Thank you!

salvo · Post by **salvo** » Sat Sep 29, 2007 12:42 am

Did you inspect the crown for any imperfections and make sure the Lyman is fastened good and tight and operating correctly?

Kansas Ed · Post by **Kansas Ed** » Sat Sep 29, 2007 12:44 am

71fan,

We recently experienced a wide spread in SD with a tried and true load in our 38-72's. I'm talking about 200 fps extreme spread. Traced it back to the Hornady 1-shot lube we were using. We didn't give it enough time to dry after sizing, and before loading. I think I would load a fresh batch if I were you and allow the lube to dry overnight before charging and see what effect it has on your load. I believe that when damp, the 1-shot lube was contaminating the powder over time and creating the problem.

Ed

95fan · Post by **95fan** » Sat Sep 29, 2007 1:02 am

I Have a browning 71 that shoots just fine that you can borrow.

Have you checked the COL to see if the crimps have failed causing inconsistant lengths.

Have you removed the forend to see if it is rubbing against the barrel. The humidity was quite high today and the wood could have swelled a little.

The load that you are using could be sensititive to powder position. you should try shooting by only loading one at a time paying close attention to powder position in the cartridge.

also, you should tell me before you go next time; not call me from the range.

71fan · Post by **71fan** » Sat Sep 29, 2007 1:19 am

Kansas Ed wrote:71fan,

We recently experienced a wide spread in SD with a tried and true load in our 38-72's. I'm talking about 200 fps extreme spread. Traced it back to the Hornady 1-shot lube we were using. We didn't give it enough time to dry after sizing, and before loading. I think I would load a fresh batch if I were you and allow the lube to dry overnight before charging and see what effect it has on your load. I believe that when damp, the 1-shot lube was contaminating the powder over time and creating the problem.

Ed

Kansas Ed,

I don't lube my jacketed bullets...do you

71fan · Post by **71fan** » Sat Sep 29, 2007 1:22 am

salvo wrote:Did you inspect the crown for any imperfections and make sure the Lyman is fastened good and tight and operating correctly?

Salvo,
The crown looks good. The sight does have a very slight wobble to it, but it's always been like that. All the mounting screws are tight; its the slide that has a tiny bit of play in the mounting plate. I'll try to shim it or something to tighten it up.

Thanks for the suggestion.

71fan · Post by **71fan** » Sat Sep 29, 2007 1:28 am

95fan wrote:I Have a browning 71 that shoots just fine that you can borrow. No comment

Have you checked the COL to see if the crimps have failed causing inconsistant lengths. They were all trimmed prior to loading.

Have you removed the forend to see if it is rubbing against the barrel. The humidity was quite high today and the wood could have swelled a little. This is where I think I may have a problem. It was very humid today and my safe has a de-humidifier. I guess I'll pull the forearm and at least take a look. But the 1886 and Marlin 39A live in the same safe and shot great today.

The load that you are using could be sensititive to powder position. you should try shooting by only loading one at a time paying close attention to powder position in the cartridge. It's been fine before...I doubt this is an issue. Anyway, I do switch between a charged magazine and single shot, and I didn't notice any difference.

also, you should tell me before you go next time; not call me from the range. I needed alone time

cubrock · Post by **cubrock** » Sat Sep 29, 2007 5:29 am

This may or may not be helpful, but I've had this happen with other guns and found the culprit to be a loose action screw somewhere. Have you checked all the screws on the gun?

Best of luck! It stinks to have a gun go sour right before a big hunt!

Malamute · Post by **Malamute** » Sat Sep 29, 2007 9:16 am

By chance, are you shooting with a tight sling? Shooting with a sling can change POI on some lever guns.

My first thought was the fore end causing the problem. If it's tight as you say, it could be too tight and causing pressure. I for one don't mind a slight bit of play in the fore end, as I know it isn't binding or causing pressure on the barrel. BTW, when you get to Wyoming, within a couple days or so, the fore end will likely loosen up, no matter how tight it is back home, if you come from someplace that's humid. Wyoming is usually very dry. Might be a good idea to take enough extra rounds to check zero after being here a few days, and resight if needed.

You might try removing the fore end cap screws and shooting it to see if it groups better.

Where in Wyoming are you headed?

Kansas Ed · Post by **Kansas Ed** » Sat Sep 29, 2007 10:53 am

71fan wrote:
Kansas Ed wrote:71fan,

We recently experienced a wide spread in SD with a tried and true load in our 38-72's. I'm talking about 200 fps extreme spread. Traced it back to the Hornady 1-shot lube we were using. We didn't give it enough time to dry after sizing, and before loading. I think I would load a fresh batch if I were you and allow the lube to dry overnight before charging and see what effect it has on your load. I believe that when damp, the 1-shot lube was contaminating the powder over time and creating the problem.

Ed
Kansas Ed,

I don't lube my jacketed bullets...do you

Hornady 1-shot happens to be case lube......

71fan · Post by **71fan** » Sat Sep 29, 2007 10:57 am

Kansas Ed wrote:
71fan wrote:
Kansas Ed wrote:71fan,

We recently experienced a wide spread in SD with a tried and true load in our 38-72's. I'm talking about 200 fps extreme spread. Traced it back to the Hornady 1-shot lube we were using. We didn't give it enough time to dry after sizing, and before loading. I think I would load a fresh batch if I were you and allow the lube to dry overnight before charging and see what effect it has on your load. I believe that when damp, the 1-shot lube was contaminating the powder over time and creating the problem.

Ed
Kansas Ed,

I don't lube my jacketed bullets...do you
Hornady 1-shot happens to be case lube......

OOOHHH. I see. That's embarrasing. OK, so now you have my attention. How is the case lube getting inside your cases. I roll my cases in RCBS case lube but never figured on case lube being able to contact the powder. How does the 1-shot work and should I be using it?

J Miller · Post by **J Miller** » Sat Sep 29, 2007 11:49 am

It has been my experience that case lube will eventually coat everything inside the sizing die. So some of it getting inside the case is very possible.

Since I also lube the inside of my case necks so the expander has an easier time coming out, I simply tumble my cases after sizing them.
No problems them.

Joe

Kansas Ed · Post by **Kansas Ed** » Sat Sep 29, 2007 4:27 pm

Hornady 1-shot is a spray on lube. And I intentionally get it inside the case necks for easier sizing. Even though it says that it "Will not harm powder or primers" I believe they meant that it won't contaminate them after it has thoroughly dried...some of our loads obviously hadn't enough time to dry completely.

Ed

Modoc ED · Post by **Modoc ED** » Sun Sep 30, 2007 11:05 am

I use "Lee Sizing Case Lube" in the 2 oz tube. It is slow but has a wax base that will not contiminate powder or primer. They say to put it on with your fingers but I experimented with a new RCBS Pad the last time I reloaded and coated it with the Lee lube and it worked fine and was much faster than using my fingers although, I do get more of an up-close and personal, fuzzy, feeling when lubing my brass with my fingers. I use Q-tips to lube the inside of the case neck.