So I've had this sick beat 320 compact for several months now.

When I first got the gun to the range it had issues shooting low. Sig's customer service was very good and they sent me a replacement front (the number 8 that matches the number 8 rear sight for 9mm).

Most of my shooting has been combat/silhouette shooting. As a result I wasn't as aware how low it was still shooting. Today we are still seeing groups about 3 inches low at 15 yards. The question is, is there another site combination? Or do I need to send it back to sig?

Has anyone else dealt with this?

This message has been edited. Last edited by: bcjwriter,

What bullet weight? Top edge of front sight on intended poi? Dot on poi?

First, the usual questions:

1) Have you shot it off a bench/rest? Or just unsupported?

2) Have you had another shooter do the same?

3) Doe above.

In other words, shooter or incorrect sights?

My own P320C 9 mm came with 8/8 sights. What sight # was originally in the gun? Presumably, they gave you a lower front sight (higher number) to raise the POI.

Here's a link to a comprehensive explanation of the Sig sight numbering system:
https://www.realgunreviews.com...ights-sight-numbers/


At 25 yards (excerpt):
Raising the front sight one number raises the POI by 1″
Lowering the front sight one number lowers the POI by 1″
Raising the rear sight one number raises the POI by 2″
Lowering the rear sight one number lowers the POI by 2″

Ok to answer those questions...

Not shot from a rest but I was pretty rock solid with no movement in my front sight while shooting. My fellow range staff Aldo shot with identical issues. (Both of us are experienced shooters...)

POA vs POI - I'm holding my front sight directly on the target or my desired POI.

Finally ammo is 115 he American Eagle - which usually shoots very close to our duty rounds, 147 HST (standard velocity or nom +P).

I may have underestimated how low it is. Call is 3-4" at 15 yards and 6-8" at 50.

Original sight set was a 6 front and an 8 rear. They sent me an 8 for the front which is what is on it now.

Thanks for the response. However, you're chasing ghosts until you shoot the pistol off of a rest of some type.

Forget the "experienced" part. No offense, but after 50 years of shooting and 25 years of instructing, I've had issues where I thought I knew what was happening and later discovered I didn't. I've also had "experienced" students I've instructed who swore they weren't doing what I observed them doing. It's a combination of human nature and focusing on other shooting components while overlooking others. It happens with all of us.

Whatever the issue, you have to definitively eliminate the human part to make sure it is a hardware problem. In this case, shooting off a rest will accomplish that. If the bench shows the same result, you'll also have more credibility when Sig looks at it.

Finally, if it's a hardware problem it's nearly beyond playing with sight combinations. I'm using the referenced article as a guide. With 8/8 shooting 6-8" low at 25 yards, most you can do to raise POI is 10/10. That will give you a total of 6" higher (2" front + 4" rear). That's an extreme sight setup. I can't recall ever seeing a correction like that on any Sig here on the forum. Just noticed: In your post you used 50 not 25 yards as I referenced above. If 50, you have to extrapolate the adjustments, since the sight info basis is 25 yards.

I make no claim to expertise here, so if I'm in error I'm sure a fellow SF member will chime in.

Finally, just an observation on my own classic P-series and my P320's. With classic Sigs, when I acquire the shooting grip, there is only ONE position for my hand. With the P320, I have to consciously make sure the grip is slightly higher and locked into the beaver tail. Otherwise, my trigger finger will make contact lower on the trigger and has the potential for pulling downward on the gun at firing time.

I've observed the same issue in our classes with a number of novice Glock shooters. Once the grip is adjusted higher, the low shots disappear.

Once again, if it's the gun itself, it's an anomaly. Good luck.

Has anyone else fired the gun...with the same results?

I am inclined to think the problem is you.

In any case, a shorter front sight and/or taller rear sight will raise the POI.

quote:

Originally posted by GaryBF:
Has anyone else fired the gun...with the same results?

I am inclined to think the problem is you.

Yes. Same result.

I saw a 9MM P250C shoot like this.

I was at the range shooting some of my stuff and a young guy was trying to get his P250C to shoot right. He was having issues with POI and asked the RO, then me to shoot it.

Both the RO and I rested from the bench and shot a number of rounds (25-30 each) at 10 yards. It was a solid 6-7 inches low, even covering the target with the front sight (SIG "combat sighting and all ).

Tried his ammo (WWB) and what I had (PMC and Speer TMJ), it was just a fucking dog pistol and I told him it should go back.

Like others have recommended, I'd bench the thing and take as much human error out of the process as possible.

But there are numerous sight options for raising the POI further if that's what's needed. Stock 8/8s, both front and rear, are .160 tall (above the slide). You can either use the stock #8 rear and buy a shorter front or you can purchase a new set that will achieve what you want.

For reference, going from a .160 to a .150 tall front will raise the POI approximately 2" at 25 yards on the 320 compact.

More info here...

https://dawsonprecision.com/sight-calculator/

Just a thought... How is the lockup on the hood? If it is too deep then it will shoot low. Maybe it was attacked by a rogue file sometime in the past?

My P320 came with a #6 front, and #8 rear. It shot to POA, with the hit falling under the front sight's dot at 15m

I ordered Trijicon HD's for it in the standard Sig 9mm #8 front, #8 rear and didn't realize mine had a #6 front until I had them switched.

I'll shoot it this weekend, to see, but I'm already kicking myself for not looking before I ordered the HD's.

As I recall, higher numbers hit higher on target. If you went from 6 front sight to an 8, then you should have hit 2" higher not 6" low

Didn't anybody read the link I provided in my first post?

https://www.realgunreviews.com...ights-sight-numbers/

It's a COMPLETE explanation of the entire Sig sight numbering system. Sight #'s, effect on POI, pistols, calibers, dimensions, sight adjustment process, Sig sight picture, etc.

OK, to put this thread to rest. I took the advice above, and did some shooting from a bag rest. Both with my practice ammunition, and my duty ammunition. I am embarrassed to say it was the nut behind the trigger and not the gun. Again was dead on accurate, which is a relief to me. That means I don't go selling it or sending it back to Sig.

7, 10, and 15 it was dead nuts accurate. At the 25 I finally saw it. I dipped the front sight just barely - but enough to put me 4-6 inches low at 25. Time for more dry firing practice...

All's well that ends well. Nothing to be embarrassed about. Thanks for the update.

Per my July 19 post, check your grip position. It could be that simple.

It happens to everyone. Few are man (or woman) enough to admit they're human. Every new HK owner says their HK must be defective because it shoots low and left. I experienced it as well but figured out it was me.

Glad it's resolved, but I still wonder about the ammo difference. I would almost expect 115gr to print lower than 147. Maybe not much of a difference between 115 and 124, but 147 is a big step. There must be some shift, though maybe (and thankfully) not significant enough to be a problem.

Glad that you resolved the issue, and told us about it.

I'm glad you got it resolved. AE 115 gr = 147 gr? I would think 147 gr shoots low compared to the lightweight. 115 gr must not be very pew pew.