First Round Hitting High

[azdover]

Took my H012GML with a VX-FREEDOM 1.5-4X28 IER Scout scope to the range this morning trying to do some load development. I use Federal 158gr JSP (AE357A) as a baseline since I've had good luck with it in the past. I was shooting 50 yards off a concrete bench using a bipod and with a bag under the stock. I used 5 shot groups to warm up a little and check my scope alignment. My first 2 groups started out with the first shot being about 1.5- 2" high and then the next 4 grouping nicely around the POA. I was loading the first round through the ejection port and then next 4 from the magazine
using the lever.

At first, I thought the high first round might be due to lack of shooter ability. After the second group, I was wondering if loading the first round through the ejection port might be causing the high first shot. My next three 5 round groups were all loaded through the side gate and then cycling the lever. I was still getting the same 1.5-2" high flyer and then the next 4 shots grouping around the POA.

50 yards may not be stretching it out and I'm not that good a shot. Five groups may not be a large sample but I think I'm seeing a trend here. During my last group with the Federal factory rounds I applied a little Kentucky windage and aimed about 1.5" low. That shot hit close to the X and then the following 4 grouped nicely around it.

I then ran my 50 hand loads with 5 different powder loads of N110/AA9 under some Montana Bullet Works 156gr flat nose gas check hard cast lead bullets. I tried both loading the first round through the ejection port and loading all from the magazine. Didn't make a difference that I could see. I saw the same trend with 8 of the 5 round groups. I did find one N110 load that produced some promising results with out the first round high flyer. It was only 10 rounds so I'm going to load up another 50 to make sure it wasn't a fluke

Any hints or suggestions would be greatly appreciated.
Pete

[GunnyGene]

Took my H012GML with a VX-FREEDOM 1.5-4X28 IER Scout scope to the range this morning trying to do some load development. I use Federal 158gr JSP (AE357A) as a baseline since I've had good luck with it in the past. I was shooting 50 yards off a concrete bench using a bipod and with a bag under the stock. I used 5 shot groups to warm up a little and check my scope alignment. My first 2 groups started out with the first shot being about 1.5- 2" high and then the next 4 grouping nicely around the POA. I was loading the first round through the ejection port and then next 4 from the magazine
using the lever.

At first, I thought the high first round might be due to lack of shooter ability. After the second group, I was wondering if loading the first round through the ejection port might be causing the high first shot. My next three 5 round groups were all loaded through the side gate and then cycling the lever. I was still getting the same 1.5-2" high flyer and then the next 4 shots grouping around the POA.

50 yards may not be stretching it out and I'm not that good a shot. Five groups may not be a large sample but I think I'm seeing a trend here. During my last group with the Federal factory rounds I applied a little Kentucky windage and aimed about 1.5" low. That shot hit close to the X and then the following 4 grouped nicely around it.

I then ran my 50 hand loads with 5 different powder loads of N110/AA9 under some Montana Bullet Works 156gr flat nose gas check hard cast lead bullets. I tried both loading the first round through the ejection port and loading all from the magazine. Didn't make a difference that I could see. I saw the same trend with 8 of the 5 round groups. I did find one N110 load that produced some promising results with out the first round high flyer. It was only 10 rounds so I'm going to load up another 50 to make sure it wasn't a fluke

Any hints or suggestions would be greatly appreciated.
Pete

Maybe we can eliminate one possible source of this behavior. Try waiting 4 or 5 minutes for the barrel to cool between each shot and let me know what happens. Leave the bolt open while you wait.

[5shot]

My first question is did the first shot flyer happen with factory loads? Were you switching back and forth between AA9 and N110? In my experience the first shot with a different powder than what was used with the previous group will usually be a flyer. Hope this helps.

[azdover]

I think I might have found my problem. It could be shooting jacketed bullets after lead, even if they have a gas check, without cleaning the barrel.

When I started noticing the trend, I shot five 5 round groups with jacketed factory Federal. The next 50 rounds were home rolled MBW 156gr gas checked lead bullets loaded over 3 different N110 weights and 2 different AA9 weights of 10 rounds each. I saw the same trend with all except for one N110 load. With a such a small sample size that one load was probably just luck.

I ran across some posts in a rimfire forum on how carbon ring residue would affect the POA of a group. Something about the first round in a group would be adversely affected by the cold “mud/sludge” from carbon and bullet lube from previous shots. The following shots would group nicely after the first round warmed up the “mud/sludge” (their terminology - not mine).

Like I said before, Federal factory 158grJSP had always shot well in my rifle. Then I remembered I had fired some lead gas checked bullets on a previous range session. That was the first time I had fired lead bullets in my rifle and I had not cleaned the barrel afterwards. I was under the impression that gas checked lead bullets wouldn’t be a problem if I switched back to jacketed bullets.

The fix for the rimfire “mud/sludge” problem was to clean the barrel immediately in front of the chamber without removing the lead “seasoning” in the rest of the barrel. All these highly technical terms read like a manual on cooking and gardening rather than shooting.

Wondering if I might have some “mud/sludge” from the previous range session due to leading, bullet lube and carbon residue, I cleaned the barrel thoroughly. Next range trip, I fired 10 rounds of jacketed hand loads in my newly cleaned barrel at 50 yards to “season” the barrel. I also added some lemon and basil (not really). The first 3 shots weren’t that close to POA. Then the next 7 started to group nicely. I then shot two separate 5 round groups of jacketed Federal factory ammo and got two 1” groups at the POA, which is great shooting for me. I waited about 15 minutes and then shot two more 5 round groups with same results. Not exactly a large sample size, but definitely a move in the right direction. I figured I’d quit while I was ahead plus I was running out of factory ammo.

I normally don’t clean my guns after every range session when using copper jacketed ammo. Usually a quick pass with a Bore Snake and a little oil on the major moving parts. Maybe a personal lesson learned here is there might be some truth to this “mud/sludge” idea when using lubed lead bullets, even if they have a gas check. I’m definitely going to clean my guns now when switching between jacketed and lead bullets.

[Bake]

In my opinion only, each shot of the group should be shot from the same barrel, I.E. clean cold barrel. This would require a longer wait between shots and running a swab/patch and a brush through your barrel after each shot.

I am not a hunter, but I would assume the first shot is the most important shot followed by the second shot and why bother with a third?

When I competed, I would try to duplicate match conditions ( 5 or 10-round groups and with time limitations ), when I took my rifle to the range for load development and general practice . . .

[azdover]

In my opinion only, each shot of the group should be shot from the same barrel, I.E. clean cold barrel. This would require a longer wait between shots and running a swab/patch and a brush through your barrel after each shot.

I am not a hunter, but I would assume the first shot is the most important shot followed by the second shot and why bother with a third?

When I competed, I would try to duplicate match conditions ( 5 or 10-round groups and with time limitations ), when I took my rifle to the range for load development and general practice . . .

I understand. There are different procedures for different situations. I don't compete and I don't hunt. I just happen to like things that go bang so I shoot for fun. And maybe practice for a possible Zombie Apocalypse. Probably won't be cleaning my barrel after every shot in that case.

What generated my post was I'm suddenly getting first round fliers when I wasn't before. I'm no expert but this started after I had shot some lead bullets for the first time through this rifle. Maybe the mysterious 'mud/sludge?" Hell, it could have solar flares for all I know. Been a lot of those lately.

All I know is a thorough cleaning seems to have solved my problem for now.