case gauges .223 JP Rifles vs Dillon

[Quag]

I had my loading confidence shaken today at the range (not a new experience). For the first time in years I had a reloaded .223 round failure to go into battery on my JP AR-15. I can deal with light primer strikes and crimping issues and solve them but I am at a loss on this failure. The attached picture (for those of you that like pictures) shows the red JP Rifles Case gauge on the right and the Dillon Gauge on the left (of the offending round). I checked the OAL on the round at it was 2.243 vs a goal of 2.24.

 

The offending round checked out in the Dillon case gauge but would not "chamber" in the JP rifles's gauge. I have heard that you should use the gauge made for the chamber of the rifle. The JP rifle gauge says 2.23/5.56 Wylde, the silver Dillon gauge says .223 case gauge. I have have used both gauges for years and noticed the JP gauge is tighter than the Dillon but not by much and all rounds generally check out in the Dillon Gauge. Usually they both agree this is the first major difference I have had.

 

Anybody have any thoughts on the this? BTW The resizing die is a Dillon on a 650. I thought the .223/5.56 Wylde chamber was more forgiving than a pure .223 chamber but I don't remember where I read that. Seems to be the opposite.

 

Thanks for your assistance

[Guy Neill]

As I understand the chambers, the 223 (SAAMI) chamber has a short leade.  The 5.56mm chamber has a fairly long leade that has not hhad the greatest reputation for accuracy.  The Wylde chamber somewhat splits the difference, giving a longer leade than the SAAMI chamber, but shorter than the5.56mm.

 

With respect to chambering a cartridge, since the two gauges are accepting the cartridge, but the chamber is not, the chamber has some difference than the gauges, obviously.  Could this be dirt or debris in the chamber interfering?  Have you tried chambering the round again?

 

Areas of concern include the bullet contacting the rifling, the neck diameter, the position of the case shoulder and the degree of sizing on the case body..  'I do not know where the Dillon sizing dies falls with respect to sizing the case body.  Standard RCBS and other dies do not size all the way down the body of the case.  A small base sizing fie sizes further down compared to the standard sizing die.

 

The case neck diameter may be affected by a case having a thicker than normal case wall, or, perhaps, a random oversize bullet giving a larger OD.

 

If the sizing action did not bump the case shoulder back sufficiently, that would interfere with chambering.

 

You might blacken the cartridge and try it in the gauges and the chamber, looking for the contact points.  That may enable you to determine the source of the problem.

 

 

[Quag]

Guy thanks for your response.One thing you may have not understood from my post is the Wylde Case Gauge (JP-Rifles red) did not accept the cartridge, the Dillon gauge did. I did re-chamber the cartridge again and it would not seat.  From the marks on it it looks like it is hung up about 3/4 up the cartridge or 1/4 below the case rim. Later today I will blacken it and see exactly where it is hanging up and caliper the diameter.

 

One of the reasons I use the Dillon resizing die is that it is supposed to resize the entire cartridge (at least that is what I was told). I guess I will contact Dillon and try to find out what the specs are on their gauge. Perhaps the JP-Wylde gauge is narrower than the Dillon gauge. Why I'd like to find that out. 

 

 

 

 

[Tom Freeman]

Gauges are fine, but keep in mind that they are not an exact clone of your chamber.

 

Your picture looks like there is a rub mark where the shoulder and body meet.  I would guess you are not bumping the shoulder back enough when you FL resize.

[bigedp51]

The JP Enterprise case gauge is smaller in diameter and closer to minimum SAAMI body diameter.

 

Below a Wilson, Dillon and JP Enterprise .223 case gauges, I have placed the cases base end first into the gauges to show how much smaller in diameter the JP Enterprise gauge is.

 

 

In a semi-auto the case body diameter after full length resizing should be .003 to .005 "SMALLER" than its fired diameter. This allows the case to spring back from the chamber walls when fired and extract reliably.

 

If your resized cases will not drop all the way into the JP Enterprise gauge it means the die is not reducing the case body diameter enough. If you are using once fired or range pickup brass you might be dealing with brass spring back after sizing. Meaning the case was fired in another chamber and you might need a small base die to reduce the body diameter more.

 

NOTE, I'm loading for three AR15 rifles and use bulk once fired Lake City brass and size them the first time with a small base die. This brings the case back to minimum SAAMI diamentions and allows the case to chamber in any .223/5.56 rifle.

 

No matter what type full length die is used the case springs back larger after sizing. And the bigest problem comes from cases fired in another chamber and the die not reducing the case body diameter enough. I check the resized cases with the JP Enterprise and again performing a plop test with my loaded rounds. If the resized case fits the gauge but a loaded round does not, normally the case neck is bulged because the seating die is not setup properly. Meaning seating and crimping in the same operation and creating a bulging crimp.

 

Below another example using .308/7.62 case gauges.

 

Below a "FIRED" Lake City case in a Dillon case gauge, and the case body diameter is preventing the case from dropping all the way into the gauge.

 

 

Below the same "FIRED" case in a JP Enterprise gauge and showing its smaller diameter. So remember if the case fits in the JP Enterprise gauge it will chamber in any .223/5.56 rifle because it is closer to minimum SAAMI case body diameter.

 

 

Bottom line, my guess is your problem is brass spring back after sizing or a bulging crimp. Meaning you may need a small base die and seat and crimp in seperate operations. I would color the compleat cartridge with a black felt tip marker and see if you have any marks when chambering a round in your rifle. Then again dropping a loaded cartridge in your JP Enterprise gauge.

 

Below three types of Forster .308 dies.

 

Edited June 20, 2020 by bigedp51

[99mpower]

Id take the upper off the AR, and chamber check some rounds. I'd make die adjustments til the brass will chamber. Are you using a full length size die or Small base? I dont like small base dies, as you are undersizing the brass. To get the brass back to specs, ROLLSIZING is the correct way to do it, not undersizing it

[Chills1994]

43 minutes ago, 99mpower said:

Id take the upper off the AR, and chamber check some rounds. I'd make die adjustments til the brass will chamber. Are you using a full length size die or Small base? I dont like small base dies, as you are undersizing the brass. To get the brass back to specs, ROLLSIZING is the correct way to do it, not undersizing it

I had asked this question before here.  It was maybe 6 months to three years ago that I asked about Case Pro plates for .223 (and possibly .308).  I was/ kinda still am having concentricity issues (a.k.a. runout issues) with my .223 rounds.

 

IIRC, the Case Pro only gets or squishes down so far on a .223 case .  Again, IIRC, those same replies said I would still have to run the Case Pro’ed brass through a full length sizing die.

 

To me, that seems less than ideal... to have to handle brass 2 or 3 times.... off the Dillon....through a Case Pro... through the 650 prep tool head ... tumble case lube off... back through the load tool head on the 650.

 

 

 

[Chills1994]

On 6/18/2020 at 9:36 PM, Quag said:

I had my loading confidence shaken today at the range (not a new experience). For the first time in years I had a reloaded .223 round failure to go into battery on my JP AR-15. I can deal with light primer strikes and crimping issues and solve them but I am at a loss on this failure. The attached picture (for those of you that like pictures) shows the red JP Rifles Case gauge on the right and the Dillon Gauge on the left (of the offending round). I checked the OAL on the round at it was 2.243 vs a goal of 2.24.

 

The offending round checked out in the Dillon case gauge but would not "chamber" in the JP rifles's gauge. I have heard that you should use the gauge made for the chamber of the rifle. The JP rifle gauge says 2.23/5.56 Wylde, the silver Dillon gauge says .223 case gauge. I have have used both gauges for years and noticed the JP gauge is tighter than the Dillon but not by much and all rounds generally check out in the Dillon Gauge. Usually they both agree this is the first major difference I have had.

 

Anybody have any thoughts on the this? BTW The resizing die is a Dillon on a 650. I thought the .223/5.56 Wylde chamber was more forgiving than a pure .223 chamber but I don't remember where I read that. Seems to be the opposite.

 

Thanks for your assistance

have you used a Hornady  case comparator (the little dealie-oh that clamps onto your digital calipers jaws) to see if you are bumping the shoulders back far enough (or too far)?

 

how are you trimming your brass?

[99mpower]

3 minutes ago, Chills1994 said:

I had asked this question before here.  It was maybe 6 months to three years ago that I asked about Case Pro plates for .223 (and possibly .308).  I was/ kinda still am having concentricity issues (a.k.a. runout issues) with my .223 rounds.

 

IIRC, the Case Pro only gets or squishes down so far on a .223 case .  Again, IIRC, those same replies said I would still have to run the Case Pro’ed brass through a full length sizing die.

 

To me, that seems less than ideal... to have to handle brass 2 or 3 times.... off the Dillon....through a Case Pro... through the 650 prep tool head ... tumble case lube off... back through the load tool head on the 650.

 

 

 

 

im not familiar with the Case Pro.. .is that a rollsizer? should be rolling the case head, not the middle/upper part..

 

If its not working the way you want, Id trim brass on the Dillon with a RT1500 and carbide size die, and after trimming is done, re-size again with a Small base die in station 4 or 5 depending on how you have it set up

 

www.rollsizer.com

[Chills1994]

Yes a Case Pro is a roll sizer.

 

it has two steel plates.

 

one is fixed or stationary.

 

The other plate moves in a linear motion .

 

at that time (and going back to say 2007), the Case Pro was the only roll sizer I ever knew about.

 

 

[Quag]

20 hours ago, bigedp51 said:

The JP Enterprise case gauge is smaller in diameter and closer to minimum SAAMI body diameter.

 

 

Thanks for your in depth reply, your "spring back theory" has a lot of merit. I shot over 100 rounds today in a 3 gun match with my AR-15 with all reloads. I checked 200 rounds with the JP gauge last night. All of them passed the drop test with the JP gauge except 3. I had no problems at the match. Great accuracy at 100 yards shooting freehand. I believe the issue is due to either spring back or short stroking during resizing on my 650 (or both). I use a Dillon 223/5.56 resizing die which is supposed to be a full length die. Thanks for the info on the differences in the case check gauges. Its amazing how different they are for the same round.

 

I am going to switch to a different brass prep method that may help with this. But from now on any match reloads go in the JP rifles Wylde case gauge that's the final QC check. JP rifles does recommend using their case gauge when reloading, I just checked my notes from 4 years ago when I bought my JP AR-15. I don't know why I got into using the silver Dillon gauge.

Edited June 21, 2020 by Quag
BTW the 3 rounds that failed the JP gauge last night were all Lake City, coincidence or is there something to it

[MakBaba]

The Wilson gauge is only concerned with base to shoulder. The neck and body diameters are left loose. You measure your fired case in the gauge so you get an indication of your chamber size. Then just bump your shoulder back .003 or more and your good to go. 
My B/A 5.56 barrel measures 1.771 while my BCM 5.56 NM barrel measures 1.768. It’s so consistent that I can gather my brass after shooting and tell which gun it was shot in (probably irrelevant info). I usually set it to 1.765 to minimize working the case. The trick is, when using mixed brass, that the heavier brass (CBC, Norma, MEN) will come out long if I don’t dial in more bump.

 I haven’t found OAL to be relevant to reliability  as long as it will run through the magazines.