Anyone solve the first shot low and left phenomenon?

[Darryle]

I got this 10 times. Though I am impressed with the Sigma and it's accuracy at 20yds even shooting the cheap aluminum Blazer 165gr ammo.

Sent from my Tesla coil

 

[JPriest]

I've had the same thing happen with my M&P45. I can only think I am anticipating recoil too much, or haven't mastered the trigger yet. I am really impressed with the gun and on my best day put the next 5 shots through a hole the size of a quarter, so it definitely is not the gun. Funny thing is, it doesn't happen to me with my revolvers (I always shoot double action), even with the big .44mag.

I'd be interested to hear what others think the cause might be so I can correct it.

 

[wewaslim]

Too much finger on the trigger. Just use the pad of the first joint of the trigger finger. You'll be amazed at how well you can shoot.

 

[GKC]

Aim high and right...

Seriously, as others have said, it's the pull you are making. There's a chart that has been posted on the forum here that breaks it down by where the shot is hitting the target, as to the likely cause (grip, trigger pull, etc.) If I can find it again, I'll post it here.

 

[Darryle]

It did every time. I also only use the last half of the tip of the finger. It was only the Sigma that did it, both M&P compacts were inside the x-ring with all 15rds. I started chambering the first round by dropping it in, didn't matter whether I stripped it from the mag or loaded it manually.

While the trigger isn't as smooth as the M&P, it is close in weight. I tried it off of a rest and it still does it with the first round only.

It could be me, but I would think it would do it with all 3 pistols.

Sent from my Tesla coil

 

[wyccad915]

I got that last time too. nice grouping on the rest though, if I may say so.

 

[27 Man]

Low left usually indicates a jerk on the trigger.

 

[ditto1958]

Aim high and right...
/QUOTE]

LOL. Or... Shoot left handed. Then your first shot will be low and to the right.

 

[checkmyswag]

Slow down. Only speed up when they are all where you want them to be. Overall good shooting.

 

[Fishinfool]

Could very well be the trigger pull, BUT, it is not unknown for some semi-auto's to throw their first shot out of the group of subsequent shots. This first round "flyer" phenomenon has been well documented in a variety of semi handguns and rifles.

Larry

 

[rwsmith]

Maybe....

Maybe after your first shot your grip tightens into a more correct position. Just a guess that would explain why the first shot is the low one.

 

[Darryle]

For the $300 I have invested in it, it will make a fine boat/truck gun.

I just cant explain why it did this all 10 times I shot a full magazine(150rds) and I never saw it once with the 800+rds I put thru the M&P 40c's.

I even tightened my grip anticipating the low and left and it still did it. I shot it off of a rest and it still did it. It ha me scratching my head.

Thanks so far for the suggestions. I will head back out to the farm tomorrow and run another 3-400rds thru it and see what it does.

 

[a62rambler]

Try loading one round less in the mag and see if you still get the first round flyer. I have an idea but I don't want to risk a placebo effect.

 

[Rpg]

Try loading one round less in the mag and see if you still get the first round flyer. I have an idea but I don't want to risk a placebo effect.

I think you've solved the problem a62rambler! I agree with your hypotheses! Very astute.

 

[wmk6341]

Just a thought. All but the first are being shot from reset. Could that be the difference?

Limiting magazine capacities is about as effective as limiting the size of beer bottles.

 

[Darryle]

I think I know where he is going with this, I plan to fire the first round without the magazine to fully eliminate the chance of it actually being the cause.

I didn't have a chance to go to the farm yesterday, but after work this morning I will be heading out there to put 50 thru it to see.

Sent from my Tesla coil

 

[ralph7]

Try shooting one round in the ground and then start a group with the remaining rounds.
I bet you get no fliers.
Think it might have something to do with the speed of the slide slamming the cartridge in after firing, that doesn't happen when you manually close the slide on that first round.

 

[JPriest]

Try loading one round less in the mag and see if you still get the first round flyer. I have an idea but I don't want to risk a placebo effect.

I tired this today with my M&P45 and it didn't make a difference. Mind you, we're limited to 10 round mags up here anyways, so 9 instead of 10 probably wouldn't make a difference.

Funny thing I did notice is that it wasn't the first shot with each mag that went low and left, but just the first shot with the gun. Mags 2-5 did not demonstrate the phenomenon.

 

[gdauth]

Low left usually indicates a jerk on the trigger.

That was not very nice!

 

[jpendergrass1]

I've had the same thing happen. When I first start shooting, I hit low left. Then, I remove the magazine and do a dry fire and I am amazed at what I do. Due to the long trigger pull, once I have it pulled back about 3/4 of the way, I start anticipating the recoil of the gun and begin putting more pressure on my grip. When I do this, I "push" the back of the gun up and with my left hand pushing as well, it goes to the right slightly. This results in the barrel going low left. This is purely because of the trigger pull, for me. I am used to the short pull of a Glock and an older S&W 9mm, since that is what I have shot before, that I have developed this set sense of the exact pressure to apply to have a shot fire. Then going to a trigger that is 9# or 8# or what-have-you, that muscle memory that I developed ends up hindering my shot of a different gun. I've tried to correct myself but those first couple shots are always way off. Instead of trying to relearn to how shoot, essentially, I have decided to just buy the Apex Tech spring kit and make the trigger pull be about the same as my previous firearms.

Another thing to keep in mind is you have a cold barrel when you first fire. The most difficult shot a sniper has at any range is the first bullet to leave his rifle because it is the least accurate. A warm barrel causes the rifling to act more efficiently. With a barrel as short as a pistol, the shot is already less accurate than a rifle, so one would assume that "shooting cold" would have much more of an effect on the trajectory of a round than it would on a rifle. Just something to keep in mind. There is a reason people "warm up" before doing any type of competitive sport.

 

[GKC]

Try loading one round less in the mag and see if you still get the first round flyer. I have an idea but I don't want to risk a placebo effect.

OK, I might as well ask a dumb question, instead of just wondering about it...

What effect would one less round in the magazine have on the first shot?

 

[jpendergrass1]

OK, I might as well ask a dumb question, instead of just wondering about it...

What effect would one less round in the magazine have on the first shot?

I'm guessing here:

Maybe when the spring of a magazine is pressed to its full extent (full mag) then it wants to release that energy more to give it relief and go back to its natural state (empty mag). With a full magazine, that spring is pushing up on the next round with much more force than it would be with 1 less round. Just like how it is easier to load the first rounds into a magazine than it is to load the last couple rounds. When it pushes with more force, it could cause the round to be loaded faster and, possibly, not set completely flat and snug. Then the gun also has that spring pushing the next round up at a high force as well to affect it also.

Honestly, like I said, I'm guessing here but you have got to take all things into consideration. I mean, a 5mph crosswind can cause changes in bullet travel and the force of that spring in a magazine is definitely higher than the force of a crosswind.

Just wait, the guy is going to come back and have some really simple answer and it is going to turn out that I am looking way to in to this because of my engineering background.

 

[snubbyfan]

Aim high and right...

Seriously, as others have said, it's the pull you are making. There's a chart that has been posted on the forum here that breaks it down by where the shot is hitting the target, as to the likely cause (grip, trigger pull, etc.) If I can find it again, I'll post it here.

Found it for ya.

 

[Darryle]

I'm guessing here:

Maybe when the spring of a magazine is pressed to its full extent (full mag) then it wants to release that energy more to give it relief and go back to its natural state (empty mag). With a full magazine, that spring is pushing up on the next round with much more force than it would be with 1 less round. Just like how it is easier to load the first rounds into a magazine than it is to load the last couple rounds. When it pushes with more force, it could cause the round to be loaded faster and, possibly, not set completely flat and snug. Then the gun also has that spring pushing the next round up at a high force as well to affect it also.

Honestly, like I said, I'm guessing here but you have got to take all things into consideration. I mean, a 5mph crosswind can cause changes in bullet travel and the force of that spring in a magazine is definitely higher than the force of a crosswind.

Just wait, the guy is going to come back and have some really simple answer and it is going to turn out that I am looking way to in to this because of my engineering background.

This was eliminated via loading the first round directly into the chamber then inserting the magazine.

I think it is tension of the full magazine on the bottom of the slide, pushing the rear slightly and therefore bringing the front down. The only thing I can't explain is why the sights moving the same way wouldn't correct it.

I maybe wrong, but I haven't had time to make it to the farm to test several different scenarios.

I'd like to meet the guy who designed the frost free outside faucet and kick him in the taint.

Sent from my Tesla coil

 

[Darryle]

Okay, here are the results of the first magazine. Other than the 180gr Winchester flat nose FMJ shooting low vs the 165gr, here are the results. I loaded the first round directly into the chamber and shot it without the magazine in place. Then let the slide strip the second round and shot the remaining 14rds.

Sent from my ADR6425LVW using Tapatalk 4 Beta

 

[a62rambler]

OK, I might as well ask a dumb question, instead of just wondering about it...

What effect would one less round in the magazine have on the first shot?

Not a dumb question at all. It could have several possible effects. I'll give some later. My idea was to first eliminate possible variables. Posters were suggesting shooter error but due to his nice groups I doubted that and was trying to eliminate other things I've seen.

Reasons a tight mag spring could cause this. Additional pressure on the rear of the slide might change the pressure on the front part of the polymer frame just enough to change how it flexes. That's just a wild guess. I know the Sigma mags have a history of being really hard to get the last round in and wanted to eliminate that variable before diagnosing the problem. I can think of several other causes. It could change the drag on the slide and the slide to frame fit or it might lift the slide enough to change the fit of the barrel lug to frame. It could cause the barrel to angle down in the front of the slide. The cause will probable remain a mystery without high speed camera work to see what was happening.

One poster said it happened to him but only on the first shot. That could be simply a cold bore flyer. That's usually only seen on rifles because most don't shoot a handgun accurately enough to see it or they shoot at shorter ranges but it is still a factor. In O'cowboy's case it was a problem with a every full mag so the first thing to look at is if the full mag is the cause. If the problem is with a full mag only then see if one round less fixes the problem. If it doesn't then look to other factors. I've seen this problem in the past and sometimes one round less fixed the problem. Not sure why it fixed it in the other cases but it solved the problem.

 

[a62rambler]

I'm guessing here:

Just wait, the guy is going to come back and have some really simple answer and it is going to turn out that I am looking way to in to this because of my engineering background.

Just noticed this response and had to laugh. I don't have an engineering background so I don't know the excuse to use in my case. I guess it's just my background in solving crimes that makes me look at eliminating things or people before looking at the motive or cause. jpendergrass is as good an explanation as any I can also guess at. And since he has an engineering background his guess probably is better than my guesses.

If one round less fixes the problem then decide if you want one more round or better first round hit potential!

 

[a62rambler]

I ruled out shooter error because it happens Once per 15 round mag and always on the first shot. That's mechanical. Shooter error would be once sometimes, twice sometimes, four sometimes, three sometimes etc... I'll post my groups and you can see shooter error in action. LOL O'cowboy was having a consistent repeatable problem and that screams mechanical issue to me.

 

[Sebring Pop]

Snubbyfan has the answer. That chart knows more than I do.

 

[Darryle]

It was definitely the pressure from a fully loaded magazines. I shot 10rds by dropping the round directly into the chamber and with no magazine and each one printed withing the same group as the remaining 14rds. I then tried 14rds, 10rds, 5rds in the magazine and load, drop the slide and run and in each instance I got a nice group at 20yds. I appreciate the tips and the very sound thinking on the reason behind it. I think this little pistol is a keeper. I cleaned up the sear block housing, removing the "flashing/parting line" on the underside where it mates with the sear, dropped another 1/4lb off of the trigger and now it is perfectly smooth.

I ran 300rds of the 180 FMJ and 250rds of the Winchester Jacketed Hollow Points thru it today and not one single malfunction. I have close to 1000rds total and it hasn't hiccuped once, even after he trigger mods.

I ordered a set of Trijicon NS from Trijicon, 8 week lead time, we'll see. I could order the Meprolight for about $70 less, but honestly, did not know how long these have been on the shelf at Midway.