OAL 9mm JHP

gwtx · Dec 26, 2020

What is the advantage/reason for loading longer oal ? I've not been loading 9mm but a year or so, and not a lot rounds in that time. In researching, I see a lot of people load to the max (PLUNK) and then back off a few thou. Most of my reloading is mimicking the Factory ammo(124 XTP +P)I use in my "carry" pistol, and I just load to the same length as the Factory stuff, or just a tad longer.
Mostly just curious.

mikerjf · Dec 26, 2020

You may find a particular gun is more reliable with a certain COAL.

Since (all other things being equal) a longer COAL will have lower pressure, some might prefer the extra safety margin when using a max load.

I imagine it's possible there might be accuracy differences with the bullet farther/closer to the start of the rifling.

Published load data should specify a COAL, you don't want to load shorter than that.

jag22 · Dec 26, 2020

Because you can, that’s why we reload. What you should be learning is that the manuals are guides that should be followed but there is leeway. I’m sure you’ve seen that many of them don’t even agree. Some people like them hot (I don’t) and some like powder puffs (don’t like them either).

OKFC05 · Dec 27, 2020

You'll find some people take factors like loading close to the rifling that matter in long range rifle and apply it to loading short range pistol because they "feel" it should make the pistol load somehow better also. It doesn't, and it can cause reliability problems with normal component variations, not to mention when you buy that new pistol and it chokes on your longer reloads because it has no freebore in the rifling. There is no industry standard for freebore, and STI competitiion pistols have a lot while some compact 9mms have none.

Nevada Ed · Dec 27, 2020

Some 9mm pistols need a short OAL to feed and eject the spent case
while others do well with the longer 1.165" maximum length.
It also depends on the bullets shape and the pistol's magazine, on what will work.

With the plated ball 115gr I start at 1.09 and go to 1.14" OAL
The larger 124 gr can start at 1.09 but can go to 1.165" OAL.
Some load the 115 out to 1.165" but I like a little more grip on the bullet.

The Berry THP or HAP 124gr bullet can have a 1.13" OAL with Unique but
it does much better at 1.075" with my faster powders. (small flake)
The 115/124 Gold Dot works best with a 1.12" OAL in my weapons.

Lots of different OAL from the companies..........
the Federal 9mm Ball ammo has their Amer. Eagle at a short 1.065 OAL.

Some pistols and powders gain FPS with a short OAL and less case volume space
but my 5" 9mm actually will drop FPS with the 115 &124 ball at 1.10 & 1.09" OAL with HS-6 and BE-86 powder.

The main goal is to get the ammo to feed.............
no matter what the OAL or the speed that it is going.

Have fun.

rwsmith · Dec 27, 2020

If you reload for short chambers...

Nevada Ed said:
Some 9mm pistols need a short OAL to feed and eject the spent case
while others do well with the longer 1.165" maximum length.
It also depends on the bullets shape and the pistol's magazine, on what will work.

With the plated ball 115gr I start at 1.09 and go to 1.14" OAL
The larger 124 gr can start at 1.09 but can go to 1.165" OAL.
Some load the 115 out to 1.165" but I like a little more grip on the bullet.

The Berry THP or HAP 124gr bullet can have a 1.13" OAL with Unique but
it does much better at 1.075" with my faster powders. (small flake)
The 115/124 Gold Dot works best with a 1.12" OAL in my weapons.

Lots of different OAL from the companies..........
the Federal 9mm Ball ammo has their Amer. Eagle at a short 1.065 OAL.

Some pistols and powders gain FPS with a short OAL and less case volume space
but my 5" 9mm actually will drop FPS with the 115 &124 ball at 1.10 & 1.09" OAL with HS-6 and BE-86 powder.

The main goal is to get the ammo to feed.............
no matter what the OAL or the speed that it is going.

Have fun.

Save yourself a lot of trouble and find a coal for each type of ammo that works in all of your guns. I loaded and shot 1000 bullets that I hated because they were so touchy in most of my guns. They couldn't be 1000th of an inch too long. In addition the coating was lumpy. (Early in the powder coat game. I should have sent them back but didn't realize how much trouble they were going to be.

gwtx · Dec 27, 2020

Thanks folks for all the good info. Your willingness to share it is much appreciated. Can't afford to do much experimenting or shooting at this time. The loads I have are working good. Like I said, mostly just curious.

noylj · Dec 27, 2020

In my guns, a longer COL gives better accuracy.
This is balanced by whether the rounds fit the magazine, feed reliably, and chamber easily.
The optimumCOL (best accuracy with totally reliable feeding and chambering) is not carved in stone and is different for each different bullet.
When reloading, establish a COL that works in your gun(s) before you ever start to reload (make up a couple of inert dummy rounds you can use for feed and chambering tests).

Nevada Ed · Dec 27, 2020

Save yourself a lot of trouble and find a coal for each type of ammo that works in all of your guns. c/o post #6

The "Ball" bullets have a large area to be set at.....
the JHP bullets not so much, so............

I guess you could set every load at a OAL of 1.12" and call it a day...........

if they work in your 9mm pistols.

rg1 · Dec 27, 2020

A guide for me when loading factory bullets such as Hornady XTP's, Speer Gold Dots, Rem Golden Sabers, etc. is to go to a local shop and ask to measure factory rounds. They will let you usually. Most 124 hollowpoints seem to be 1.120" to 1.125" oal and all I've loaded to these lengths feed and shoot well in various 9MM pistols and carbines. Use manual data for overall seating depths if different.

rwsmith · Dec 27, 2020

The ones I had were ball....

Nevada Ed said:
Save yourself a lot of trouble and find a coal for each type of ammo that works in all of your guns. c/o post #6

The "Ball" bullets have a large area to be set at.....
the JHP bullets not so much, so............

I guess you could set every load at a OAL of 1.12" and call it a day...........

if they work in your 9mm pistols.

1.06" was the absolute maximum on them. It said on the webpage to seat them there, but I thought I had SOME room to play with. I want bullets with a little taper to the profile from now on.

I have sub compacts to full size pistols. I believe the Shield gave me the most trouble (super reliable when ammo is good). Funny, the tiny Keltec,was less affected, i.e. It would shoot some rounds. Reloading 9mm was a bear for me, moreso than any other cartridge.

shil · Dec 28, 2020

Careful! All 9mm bullets of the same weight and style are not equal. Use the published data for THAT bullet at THAT COL. Don't substitute a bullet of the same weight and style using the same COL. Different jacket alloy and/or longer bearing surface = possible overpressure. Been there, done that, learned from it.

Nevada Ed · Dec 28, 2020

The only 9mm bullet that you really need to be on top of the correct OAL is the....................

147 gr plated Round nose by Berry, that I know of, due to the pressures that can build up if set too deep into the case.

I have yet to get a over pressure load from any of my manuals that I use, even with the +P loads in sturdy pistols.

Even the little 3" Kahr can take a +P load but it does not go to fast, compared with the longer barrels but it has enough energy to do the job.

As for the long OAL being better........
In my C9 3.5" and 5"pistols, the 124 gr. plated "Ball" FMJ type bullets that I use by several makers, all do better in accuracy with light to medium target loads, when they are set at 1.165".
I don't know if being closer to the lands or maybe being lower in pressure helps, but it works in my pistols.
This OAL is for target loads only.

RussellD · Jan 9, 2021

I load for a number of different pistols and carbines. My goal to is to load quality ammo that will function in everything.

fredj338 · Jan 10, 2021

gwtx said:
What is the advantage/reason for loading longer oal ? I've not been loading 9mm but a year or so, and not a lot rounds in that time. In researching, I see a lot of people load to the max (PLUNK) and then back off a few thou. Most of my reloading is mimicking the Factory ammo(124 XTP +P)I use in my "carry" pistol, and I just load to the same length as the Factory stuff, or just a tad longer.
Mostly just curious.

A factory oal is useless unless the bullets are the same.
You load long to lower pressures, maybe helps feeding, maybe more accurate.

gwtx · Jan 10, 2021

fredj338 said:
A factory oal is useless unless the bullets are the same.
You load long to lower pressures, maybe helps feeding, maybe more accurate.

Thanks Fred. I use the same bullet, xtp 124g. I also use the Everglades 124g JHP which looks and acts just like the xtp,,as far as I can tell.
My loads feed fine, my velocity is just a little slower than the +p factory loads, which is where I think I want it.
I don't quite understand the reasoning for loading longer to lower pressure, when you can do the same by using less powder. Load longer to reduce pressure(velocity), and then use more powder to get the velocity back up to where you want it. I can tell no difference in accuracy because I'm not an expert shot, and don't have a "manson"(sp) rest.
I'm satisfied with my current loads, just wondered if I was missing out on something by not loading "to the max". With the "shortage" situation, I can't afford to do much experimenting.
Thanks again for your reply.
Buckle up

growr · Jan 10, 2021

Find which factory cartridge shoots and functions best in your guns.....replicate it, making sure that it will not bind in your magazine due to over length.

Randy

fredj338 · Jan 10, 2021

gwtx said:
Thanks Fred. I use the same bullet, xtp 124g. I also use the Everglades 124g JHP which looks and acts just like the xtp,,as far as I can tell.
My loads feed fine, my velocity is just a little slower than the +p factory loads, which is where I think I want it.
I don't quite understand the reasoning for loading longer to lower pressure, when you can do the same by using less powder. Load longer to reduce pressure(velocity), and then use more powder to get the velocity back up to where you want it. I can tell no difference in accuracy because I'm not an expert shot, and don't have a "manson"(sp) rest.
I'm satisfied with my current loads, just wondered if I was missing out on something by not loading "to the max". With the "shortage" situation, I can't afford to do much experimenting.
Thanks again for your reply.
Buckle up

You asked so I was just giving you reasons. No data point for oal is really valid. So you load as long as possible in your gun with your bullet choice. Just understand that in handguns, shortening oal increases pressures, longer reduces them.
So if your load data says 1.145" oal with bullet A & you load shorter, pressures go up. So loading long is just belt & suspenders.

Nevada Ed · Jan 10, 2021

I don't have any Hornady JHP or "HAP" but I do have a Berry 124 THP that I use in my 9mm's for target work and just finding fps in my different length barrels.

I posted this on this site a while back but it does have some full standard 9mm loads with two different OAL due to the powders used.
The JHP is usually set shorter than a RN "Ball" bullet due to it's shape and one reason for the shorter OAL's in this photo.

This picture shows how a different OAL and a different powder used with a bullet in a pistol and make or break good accuracy.

Good loading.

fredj338 · Jan 11, 2021

Nevada Ed said:
I don't have any Hornady JHP or "HAP" but I do have a Berry 124 THP that I use in my 9mm's for target work and just finding fps in my different length barrels.

I posted this on this site a while back but it does have some full standard 9mm loads with two different OAL due to the powders used.
The JHP is usually set shorter than a RN "Ball" bullet due to it's shape and one reason for the shorter OAL's in this photo.

This picture shows how a different OAL and a different powder used with a bullet in a pistol and make or break good accuracy.

Good loading.

But that tells you little about oal affects on accuracy since you used diff powders. Oal can help or hurt acciracy but its not definitive either way.

OAL 9mm JHP

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