Need help with over all length, col

[smokinjim]

I loaded some 9mm to test. Was going to chronograph them.

Now I question the col.
All rounds were made with unique powder 5.7gr - 5.65 gr.
Winchester wsp primers.

First is
115gr. FMJRN my col is 1.148" to 1.152" Lyman 47th said 1.120" col.

Next is
115gr. JHP my col 1.151" to 1.155" Lyman 47th books 1.090"

Next
124gr berry plated HP same charge my col 1.140" to 1.143" Not sure what col should be.

Other books only state Min. OAL. and Max length.
Is the COL ok or shouold I redo the seating of the bullet?
Any help appreciated.

 

[Fleet]

shoot them, if you have problems then worry about it.

 

[Sunray]

Hi. Your OAL's are too long. You taper crimp? If you did, you should pull 'em and start over. Mind you, a 124 and 147 grain OAL is 1.169", so you could just shoot 'em and start over. They should fit in the mag with no fuss and nothing bad will happen. You might have some feeding issues though. Operative word being 'might'.
Takes some trial and error to get the seater plug adjusted just right. Best to do it with one unpowdered, unprimed case, then make another to confirm.
The OAL differences between the two bullets has to do with the shape. The RN's being pointed and the JHP's not.
Plated bullets use cast bullet data. They are not jacketed. Berry's does not publish any load data. Hodgdon's site has data for a 125 grain cast bullet(one grain won't matter). Not with Unique though. You'd need an Alliant manual for Unique and their site has no 9mm cast bullet data. Anyway, the OAL is 1.125".

 

[918v]

You don't have to pull them, just seat them deeper.

Your OAL will depend on the type of bullet. You don't want the OAL so ling the sides of the bullet nose are rubbing the magazine walls. You don't want to induce any malfunctions.

I load JHP RN to 1.150" or less. FMJ RN to 1.169" or less. TC to 1.120" or less.

 

[LiveLife]

I usually recommend you determine the max OAL first by using your barrel out of the pistol.

Since you have them loaded already, test each loaded bullet type by dropping them into the chamber with the barrel out of the pistol. Be sure the bullet noses are not hitting the lands of the rifling and head spacing on the case neck only. They should drop in freely with a "clink".

If they all pass the barrel drop test, next is the function test. I do this with a dummy round (no powder/primer) starting at the max OAL. Load the dummy round (or loaded round in your case) in the magazine and manually release the slide. If the round won't chamber fully/smoothly and hangs on the feed ramp/chamber, you may need to decrease the OAL. Incrementally decrease the OAL until you have reliable feeding/chambering from the magazine.

If they all feed/chamber reliably, then you are GTG. Generally, longer OAL will allow the bullet to engage the rifling faster for more consistent chamber pressure and more accurate shot groups.

 

[RidgwayCO]

You don't say out of what gun(s) you'll be shooting these rounds. For Glocks or Berettas, you can usually go right up to the SAAMI maximum of 1.169" COL. For CZs (and maybe XDs?), I've read that you'll need a much shorter COL for them to chamber correctly. The advice from bds above is good. I'd add that not only should they fall into the chamber with a "clink" sound, but they should fall freely from the chamber as well, without any marks on the bullet.

In general, loading a round longer than the "book" says is not considered dangerous because the increase in "boiler room" space results in less pressure upon firing. This assumes of course that the bullet isn't pressed tightly against the lands before firing.

If they pass the chamber test, then I'd recommend going ahead and shooting them.

 

[smokinjim]

bds and RidgwayCo thank you for your impute. Pistol is p95 ruger.
I read the link you provide dbs. Great info. All loads drop in and fall out easy. All headspace look flush or may be less. I have factory loads 9mm 115gr fmj rn oal 1.155 dropped them in barrel same affect. Same as my first loads I posted.
Looked in my Hercules reloader guide and says this load with Unique MIN oal is 1.120". Mine are at 1.148 to 1.152.
Everything should work ok if feed though is ok.

So big question is, if you use different powders you seat bullets deeper or less to control pressure?

In my first post thre OAL I said the lyman 47th book said was

If not as long as I’m between Max length and MIN length and it cycles ok I should be ok?
Thanks for help. To better under stand bullet seating depth.
:banghead:

Geeze while I'm asking questions, Can you use hp info for flat point bullets if they weigh the same?

 

[1SOW]

So big question is, if you use different powders you seat bullets deeper or less to control pressure?

When you change powders, change your load data source to one for 'that powder' with that bullet type, and start at the low end and work up. This is especially important if you are varying the published oal.

With that said, "most of the time" shortening the published oal will increase pressure and speed up the bullet. Lengthening the published oal will "usually" decrease pressures and slow the bullet. SOME POWDERS (not many) DON"T FOLLOW FOLLOW THIS GUIDELINE.

SOME powders will "INCREASE PRESSURE WITH A LONGER OAL. You add a couple of 100dredths and pressure drops---you add another couple of hundredths and pressures spike high. That's why you stay within the published guidelines for the powder you're using.

Especially when your not familiar with a powder start low and work up.
To repeat a 'saying' I used some time back: Follow published load data until you get the experience to screw up 'knowingly'.

 

[CZ57]

The OAL shown in manuals is the minimum OAL. It is the length at which pressures were taken. If you load longer you reduce pressure. Loading to match your pistols chamber is a very good idea. You can decrease the amount of unecessary bullet jump which can prove to enhance accuracy. Rugers typically have long throats so it doesn't surprise me that your loads checked out ok. European powder manufacturers use the CIP method of pressure testing and as a result you'll often notice that they use a longer OAL, as well as being comparable in pressure to our CUP standard of pressure. For example: Vihta Vouri uses an OAL of 1.142"/29mm for their JHP/FPJ bullets.

 

[smokinjim]

Thanks CZ57
I now know why all the different oal listed in books. Also only one book said MIN. oal wich made me wonder if the oal posted in other books were MIN. And that oal is what was tested.

 

[Sunray]

"...why all the different oal listed in books..." Different bullet weights and shapes.

 

[smokinjim]

Sunray, I guess I should of stated all the different oal for the same bullet weight. and same powder, sorry for the confusion.

 

[918v]

SOME powders will "INCREASE PRESSURE WITH A LONGER OAL. You add a couple of 100dredths and pressure drops---you add another couple of hundredths and pressures spike high. That's why you stay within the published guidelines for the powder you're using.

Which powders?

 

[gamestalker]

I would offer to help but my last experience with 9mm was fortunately only an ebarassin one. But that aside, just make sure your depth is as shallow as will function in your magazine and isn't touching the lands. I believe in the "clink" sound for this purpose.

 

[smokinjim]

Thanks to all who responded to my need for knowlage. I learned allot from all of you. Great forum and great People.

 

[smokinjim]

I loaded some 9mm to test. Was going to chronograph them.

Now I question the col.
All rounds were made with unique powder 5.7gr - 5.65 gr.
Winchester wsp primers.

First is
115gr. FMJRN my col is 1.148" to 1.152" Lyman 47th said 1.120" col.

Next is
115gr. JHP my col 1.151" to 1.155" Lyman 47th books 1.090"

Next
124gr berry plated HP same charge my col 1.140" to 1.143" Not sure what col should be.

Other books only state Min. OAL. and Max length.
Is the COL ok or shouold I redo the seating of the bullet?
Any help appreciated.

Shot all the reloads and all went well. Cronograph all rounds the 115 gr bullets were 1250 + or - feet per second and the 124 gr berry bullets were 1180 or so, one did hit 1213 fps. I know that's at the limit for the berry plated bullets. I think its a good reciepy for both bullet weights.
Thanks All

 

[918v]

SOME powders will "INCREASE PRESSURE WITH A LONGER OAL. You add a couple of 100dredths and pressure drops---you add another couple of hundredths and pressures spike high. That's why you stay within the published guidelines for the powder you're using.

1SOW,

Please explain which powders do this.

 

[1SOW]

918v: I've heard this is possible several times over the years and the specific powder or two were mentioned. I couldn't find the specific powder again.

I did find this reason it can happen: http://www.reloadammo.com/liteload.htm

Basically as the case gets more "empty" the powder spreads out and the primer flash can ignite it over the full length. With the wrong powder this can result in a "detonation instead of a 'burn' rate.

 

[918v]

I have detonated 2grs of Bullseye in a 357 case, so yes it can happen, but this is an extreme example of combining too little powder with too much case volume.

In the 9mm, this is an impossibility.