9mm don't fit case gauge

[ISDPCMAN]

I purchased a 9mm case gauge (2, actually, from different vendors) and NONE of my 9mm reloads (Dillon XL750 / Dillon dies) will fit the gauge! They chamber and fire fine. Reloads and NEW FACTORY ammo only go about 2/3 into the gauge.

Any idea WHY this is? One of the case gauges is a Hornady. The other is a 3rd party that specializes in case gauges (don't recall the manufacturer). All the other cartridges I reload fit into their respective gauges just fine. Just the 9mm are stubborn. I have even tried a Lee .003 undersize die and still the same issue.

[Alleycat72]

If it's a new gauge, you'll need to clean it out good. Use some brake cleaner on it.

[Boro Bullets]

Hornady gauges are very very tight. They are not forgiving at all. Even some of Hornady ammo off the shelf wont even gauge in their own gauges. Shock bottle gauges are extremely forgiving and if your ammo does not gauge in a shock bottle gauge I would suggest not shooting it.

Some of the reasons 9mm cartridges dont gauge are:

Glock bulge in the old case (need to be roll sized)

Concentricity of the projectile is not perfect (initial seating die needs adjusting)

Cases are hairline cracked (visual inspection before loading or can only be checked by a camdex processor)

OAL is not to spec 

There are several other variables but these are the major reasons.

Unless you are shooting tournament I would not use a Hornady gauge. I would suggest a shockbottle gauge for range ammo and  Wolff gauge for self defense.

Best of luck and hope this helps a little

[Darrell]

I've had a little trouble with 9mm reloads from range brass that wouldn't chamber in my Springfield 1911, which caused me to buy a Hornady gage. It turned out that some of my reloads were not concentric, as Boro Bullets mentioned above. The solution for me was to use a Lee Factory Crimp die and run those non-concentric rounds through it two or three times, rotating the loaded case a third of a turn each time. 

But since your reloads are chambering just fine, you really don't have a problem.

[deerslayer]

12 hours ago, Boro Bullets said:

Hornady gauges are very very tight. They are not forgiving at all. Even some of Hornady ammo off the shelf wont even gauge in their own gauges. Shock bottle gauges are extremely forgiving and if your ammo does not gauge in a shock bottle gauge I would suggest not shooting it.

Some of the reasons 9mm cartridges dont gauge are:

Glock bulge in the old case (need to be roll sized)

Concentricity of the projectile is not perfect (initial seating die needs adjusting)

Cases are hairline cracked (visual inspection before loading or can only be checked by a camdex processor)

OAL is not to spec 

There are several other variables but these are the major reasons.

Unless you are shooting tournament I would not use a Hornady gauge. I would suggest a shockbottle gauge for range ammo and  Wolff gauge for self defense.

Best of luck and hope this helps a little

I use a 9mm and .40 Shock Bottle and I don’t think either one is all that forgiving, at least compared to my Dillon 9 and .40.  Now those are pretty forgiving.  I would probably look for something tighter if I loaded ammo for Bullseye, but my Shock Bottle will identify potential problem ammo that usually plunks and spins in the gun’s barrel. 

[Omega]

Your barrel chamber makes the best gauge, if they chamber then there is no issue.  That being said, gauges should be somewhere between SAAMI minimum and maximum for that cartridge, preferably towards max so if it doesn't fit, then there is a sizing problem.  I always full length size all my cartridges and only use a gauge if I converted the cartridge, otherwise I just use the plunk test in my chamber.

[JustEd]

What bothers me is that you say new ammo won’t fit in gauge. Has to be some debris or preservative in the gauge chamber. 

[Grayfox54]

Field strip the gun and give the ammo the old Plunk test. If it passes, don't worry about it. 

[ken_mays]

The issue could be with the case or the projectile.  Mark the whole round with a Sharpie and see where the rub marks are when you try to chamber it in the gauge.    There is a commonly seen problem with some of the 9mm bullet profiles available where the ogive gets wide fast and this causes the round not to chamber in barrels with short throats.   Two ways to fix that -- recut the chamber to provide an adequate throat, or seat the bullet deeper.

[DWARREN123]

As long as they chamber in your tightest chamber then they are good to go.

Unless you are competing then they don't have to be perfect.

[Rockmup]

I have chamber reamers that I drop into case gauges when new, you'd be surprised.  Same with glock barrels, chambers are tight.

[gregintenn]

On 12/29/2023 at 11:22 AM, Grayfox54 said:

Field strip the gun and give the ammo the old Plunk test. If it passes, don't worry about it. 

+1

I’ve reloaded since I was big enough to pull the handle, and I’ve never once used a case gauge.

[deerslayer]

5 hours ago, gregintenn said:

+1

I’ve reloaded since I was big enough to pull the handle, and I’ve never once used a case gauge.

A Shockbottle is pretty useful if you are loading in volume at all.  I can gauge 100 rounds in a minute or so with it and I don't have to go get my gun and take it apart.  Even if f I already have my gun barrel in hand, the Shockbottle is still much faster.  Gauging 500 rounds one at a time with a gun barrel can get nerve racking. 

[Grayfox54]

I'm wondering. Do you have a "case" gauge or a "cartridge" gauge? Possibly your gauge is for measuring empty cases before reloading.