Storm Lake ported barrel shooting low? (Glock 19)

[Gregarious]

I recently purchased the Storm Lake ported barrel for my Glock 19. Today I shot it at the range for the first time and it is shooting low. The graphic below illustrates the stock vs. storm lake performance at 25 yards on a 10 inch steel plate.

http://i70.photobucket.com/albums/i...uawehflkjashdflkjasdhlf/Storm_Lake_Ported.jpg

http://i70.photobucket.com/albums/i97/alkjhlakwehakwehflkuawehflkjashdflkjasdhlf/stock_barrell-1.jpg

I shot 500 rounds total and the SL barrel shoots consistently lower than the stock barrel when all other things are equal.

Ammo: 115 grain FMJ (also tried 147 grain FMJ)
Distance: 25yards
Target: 10 inch steel round plate

Barrel: Glock 19 4.72 inch Storm Lake ported stainless steel. GL-19-9MM-472-2P-00T.

http://www.midwayusa.com/product/14...-in-16-twist-472-stainless-steel-with-2-ports

With the stock I can hit the plate 80% of the time at 25 yards.

With the Storm Lake ported I hit 20% of the time. I had both barrels at the range and swapped them out multiple times to verify and it was very consistent. Finally after seeing one round clip the bottom edge of the plate when using the SL barrel I began aiming high and then all shots were on.

Does anyone see why a barrel that is supposed to be more accurate is actually less accurate?

 

[jackpinesavages]

The Storm Lake barrel fit is a 12 o'clock hold, that's all. Says it's a "semi-drop in". Call Storm Lake and ask them yet?

 

[Master Blaster]

You can easily change out the glock front sight, so just buy a lower glock front sight and change it. They are cheap enough that you could buy two. (this is assuming you dont have night sights but even then you can call meprolight or Trijjicon and ask for the next lowest sight. Heck you can even calculate what height front sight you need by seeing how much lower the hit is at a given distance.

 

[GunNut]

Longer barrel = higher velocity
Higher velocity = shooting higher at same distance.

Either adjust your sights to work with the Storm Lake or go back to the factory barrel, IMHO.

 

[Sam Cade]

Higher velocity = shooting higher at same distance.

It is shooting lower, not higher.





It's definitely a fitment issue.

If it is shooting tight groups then a shorter front sight is in order.

 

[GunNut]

It is shooting lower, not higher.





It's definitely a fitment issue.

If it is shooting tight groups then a shorter front sight is in order.

Saw the pic and was thinking higher, darn reading too quickly.

Call Storm Lake they'll take care of you.

 

[trex1310]

I would guess there is nothing wrong with the barrel. You just
need a lower front sight. The higher velocity is causing you to
hit lower because the bullet is leaving the barrel faster.

 

[Zerodefect]

You can't swap barrels and expect POA/POI to be the same. Gun needs rezero'd. Swap the front sight.

 

[Gregarious]

Thanks for the replies. I have emailed them regarding the problem.

---
me: the barrel is shooting low

them: Are the groups tight? If the groups are tight but you are shooting low it is typically because of the reduced muzzle rise from a ported barrel

me: Are you saying that Storm Lake ported barrels shoot low by design?

them: no answer

---
so far I have only gotten voicemail when trying to call. I have not shot paper at 25 yrd to measure groups but the problem consistently goes away when I go back to the stock barrel.

To be fair to storm lake the barrel is advertised as "usually requires gunsmithing" but since it did drop right in and did cycle 250 rounds perfectly then I thought I was home free.

But if it does require a gunsmith or new sight then I don't get why the rep was blaming the porting. I'll post back if I get it resolved.

 

[northark147]

They probably didn't answer because it seems like they are dealing with a PITA who is making a mountain out a a mole hill.... If the thing groups tight, then adjust your sights and get over it... there is nothing wrong with the barrel. as you have already been told your POI is going to shift when you change barrels.

 

[9mmepiphany]

But if it does require a gunsmith or new sight then I don't get why the rep was blaming the porting. I'll post back if I get it resolved.

You just didn't understand him...I would have posted the same answer if you hadn't contacted them already.

The barrel isn't designed or fitted to shoot low, which is what you believe and what your last question to them inferred...that demonstrated to them that you didn't understand the effect that the porting would have when you ordered the barrel. The rep wasn't blaming the porting, he thought he was explaining something that you had overlooked before calling. The barrel is functioning exactly as it was designed to function.

Didn't you get the barrel with porting to limit muzzle flip/rise?

If you limit the rise of the bore-line, that would mean that the bullet would leave the barrel when it was lower in it's arc. Hence the bullet would strike lower at 25 yards. The further back, from the muzzle, that the ports are located, the more affect the ports will have on muzzle rise and the lower your bullet will strike

 

[Tom B]

First try a heavier weight bullet. You were shooting a 115gr so try a 124 and 147gr. You may also try a hotter load to bring POI up some. If still low you will need to change your sight. If your sights are stock then Glock sells different height rear sights. I don't think they sell different height front. You want to go with a taller rear. The sights have lines marked on the side to show height.

 

[trex1310]

me: Are you saying that Storm Lake ported barrels shoot low by design?

NO, that is not what he was saying. He was saying that
a ported barrel will shoot lower than an unported barrel, no matter
who the hell makes it. Get some JBWELD and cover the holes up
and see if that fixes your problem.

 

[The Lone Haranguer]

Something to keep in mind is that if you change or adjust sights to compensate for the now lower POI, changing back to the original barrel will make it shoot high. Or, you can put an adjustable rear sight on it.