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View Full Version : difference in length with various 9mm hp's (pics)


kielbasavw
04-30-2012, 8:19 PM
i came across a deal, and included was a box of mix matched ammo, and i noticed that they are all noticeably different in length, i haven't noticed this with any of the .45 i own. any insight on this topic? i had a very knowledgeable friend tell me you will typically see higher grain ammo loaded "longer". im just curious what the deal is, thats all.

From left to right: Speer Gold Dot +P, Black Talon, Winchester Silver Tip, PMC Eldorado StarFire
http://img.photobucket.com/albums/v312/ezkiel/IMAG0818.jpg

http://img.photobucket.com/albums/v312/ezkiel/IMAG0820.jpg

Mr.1904
04-30-2012, 9:21 PM
I believe your knowledgable friend is correct. Would you happen to know the bullet weights by any chance? If i'm not mistaken, higher grain bullets are longer and sit a little higher in the case.

kielbasavw
04-30-2012, 10:22 PM
i have a scale to measure in 1 gram increments. ill pull it out later and update

kielbasavw
04-30-2012, 10:23 PM
any way of telling the grain of each?

RoundEye
04-30-2012, 11:27 PM
any way of telling the grain of each?

Other they weighing them on a triple beam balance or the like? Not really. I'd day you could always look on the box, bute you said it was a mix match box. Another thing you may want to do is checkout the websites for each and see what weights they were available and and theme weight the whole bullets and see if you can rule oute any impossibilities.

CAglock20c
04-30-2012, 11:54 PM
ya, heavier the bullet, the longer it will be. its going to make the overall length of the cartridge longer because you can only push the bullet so far into the case without overly expanding it to the point it wont load correctly, or potential create too much pressure and crack the case/do damage to the gun.

fast54vw
05-01-2012, 12:40 PM
any way of telling the grain of each?

come weight them on my gold scale, the scale i weigh gold on not that its painted gold.

Capt Jack
05-01-2012, 1:39 PM
I have 147gr JHPs in my HD gun and they are noticeably longer than the 115s. Nothing to worry about, have fun!

DRAB_81
05-01-2012, 1:48 PM
The heavier bullet itself is longer, but that may not be related to the actual OAL of the loaded round. The powder charge is lower for heavier bullets, which is how the pressure is regulated, not how long the bullet is seated out. I have loaded 115/124/147gr JHP's all at 1.125" OAL, and 115/124/147gr FMJ/Moly/Plated bullets at 1.135" OAL, both with zero issues.

The OAL has more to do with the bullet profile than anything. Certain JHP profiles are wider, and aren't able to be loaded as long as a narrower profile JHP. If a wide profile JHP is loaded too long, it can contact the throat of the chamber, an not allow the slide to go into battery completely. SAAMI spec for 9mm OAL is anywhere between 1.00"-1.169", and the OAL you use will depend on the bullet profile & the chambers of your guns.

paul0660
05-01-2012, 1:51 PM
Nothing to worry about, have fun!

Some built to the gnat's *** guns have problems with nosediving and failure to feed with longer OAL.