[AR guy]

Ive been looking at load data and basic reading and I have noticed thst the hornady xtp bullets seem to have a shorter coal than most every bullet. the average coal for the 9mm is like 1.110 " - 1.120" . Why does hornady require you to seat their xtp deeper. Like my 9mm loads I did earlier this week said to have a coal of 1.120" but I used the xtp so I had to seat them deeper. why is that?

 

[JLA]

Nose profile is shorter. XTP bullets are HP TC designs, and TC designs have a shorter OAL than conventional RN designs.

 

[steve4102]

Nose profile is shorter. XTP bullets are HP TC designs, and TC designs have a shorter OAL than conventional RN designs.

^^This and the flat nose usually requires a shorter OAL that the RN to feed in most semi-autos.

 

[PanhandlePop]

Agree with the above, a shorter OAL is common with most JHP designs. Of course Hornady does not "require" you to seat the bullets deeper, rather their manual gives the OAL at which they tested. The OAL you use should be determined by the chamber of the pistol you are using and reliable function through your magazines. If a dummy round fits and functions at a longer OAL, (as long as you are within SAAMI spec) there really isn't a problem, but just be careful if you end up going to a shorter OAL. If you have to go shorter, adjust your powder load and work back up in 0.1 to 0.2 increments.

 

[AR guy]

Ok. I'm starting to notice, that any lil change that's made with the recipe you always start over and work up. Gotcha ya. Thanks.

 

[howlnmad]

Ok. I'm starting to notice, that any lil change that's made with the recipe you always start over and work up. Gotcha ya. Thanks.

That's right, always safety first.

 

[stev32k]

The Hornady manual I have (7th Edition) says to load the 115gr, 9mm, XTP to an OAL of 1.075. Lyman (49th Ed.) says 1.090 for the same bullet. The longest OAL for any 9mm I can find is 1.115 for the 124gr or 147gr most are under 1.100, and none are listed as 1.200.

 

[time2shoot]

main thing is to make shure it fits in the mag, and will cycle through the gun.

 

[AR guy]

So the oal givin is a good length for the gun tested, but it can vary from gun to gun. It's your gun that makes the finaly length decision then.

 

[woolleyworm]

So the oal givin is a good length for the gun tested, but it can vary from gun to gun. It's your gun that makes the finaly length decision then.

essentially yes, that is correct.

 

[streetbob]

Well I like to reload Hornady XTP 115gr Hollows for my 9mm, and most of my reloads fall center of the min to max charge. My COAL is 1.075" I think. Wouldn't it be fine to load them longer if the gun cycles them fine, but if you load them shorter then the recommended COAL wouldn't they spike the pressure?

 

[woolleyworm]

Well I like to reload Hornady XTP 115gr Hollows for my 9mm, and most of my reloads fall center of the min to max charge. My COAL is 1.075" I think. Wouldn't it be fine to load them longer if the gun cycles them fine, but if you load them shorter then the recommended COAL wouldn't they spike the pressure?

Yes, if you load them shorter, you will spike pressure. If you load them longer and find a sweet spot that works in your gun, then that's great.

Main thing is to work up every load from min's and double check everything. A Chrony is very valuable for checking loads and while not considered a "must have" in some cases; I do consider it a must have anytime you're going outside of manual/factory specs. By this I don't mean increasing your max loads (never safe); but rather increasing your OAL or not having specific bullet data. Especially when loading for a bolt action, when you're testing and trying to find that sweetspot in the leade to seat your bullet; the chrony is a must (doesn't really apply to xtp's ). If you're using the xtp's for small game in a revolver caliber, the fps is nice to know.

 

[streetbob]

Thanks Woolley, that is what I always thought it did. I have only been reloading for 2 years now and still have a lot to learn.