Minimum OAL question

Outlaw75 · August 15, 2014, 01:31 PM

I've noticed that most manuals seem to group the minimum OAL with the 'Never Exceed' side of the load data. Does the minimum OAL apply to the specific powder/bullet combination in general, or just to the higher end of the load range?

Example: I'm loading .357 mag 158 gr LSWC with 4.5 gr Titegroup. The max load is 5 gr Titegroup and the minimum OAL is given as 1.610. Does the OAL apply to the load in general or can I set my OAL at the SAAMI OAL of 1.59 for a 4.5 gr load?

Average Joe · August 15, 2014, 07:05 PM

The deeper you set the projectile, the more pressure you develop. The powder manufacture knows this, and tells you what the OAL is for your given load.

Outlaw75 · August 15, 2014, 07:50 PM

Yes, thanks! I was looking at load data on Hodgdon's website and noticed that the listed the OAL for the caliber/bullet combination, regardless of the number of grains.

Mobuck · August 15, 2014, 08:26 PM

OAL is often dictated by crimp groove location.

davery25 · August 15, 2014, 08:55 PM

It's really just an indicator. You'll just need to be aware that the further in you seat, the higher the pressure and that's going to be something to watch always but particularly at the higher ends of the charge range.

For my 223 using 77 grain A-Max bullets I had to seat way deeper than the manuals OAL because they needed to fit into a Tikka T3's stock magazine. It was fine for every powder except Benchmark 2 which started to give pressure signs at the higher end

snakeye · August 15, 2014, 09:14 PM

Quote:

OAL is often dictated by crimp groove location.

Can you explain that a little more

Nick_C_S · August 15, 2014, 10:34 PM

I'll explain it:

Not that it addresses the question in the original post, but if it's a 158g LSWC, chances are really good that there is a crimp groove in the bullet. You should put your calipers away and seat to that crimp groove.

Most revolver bullets have a crimp groove or cannelure (in the case of jacketed). Simply seat the bullet to where the case mouth resides at the groove and crimp it.

My first couple years of loading was strictly revolver rounds. I didn't even know why the starter kit I bought came with a set of calipers

Nowdays, plated bullets are getting popular for revolver rounds - then it's time to bust out the calipers. Then it's also time to get a taper crimp die - but that's another post.

August 15, 2014, 01:31 PM	#1
Outlaw75 Member Join Date: May 7, 2014 Location: Glendale, AZ Posts: 55	Minimum OAL question I've noticed that most manuals seem to group the minimum OAL with the 'Never Exceed' side of the load data. Does the minimum OAL apply to the specific powder/bullet combination in general, or just to the higher end of the load range? Example: I'm loading .357 mag 158 gr LSWC with 4.5 gr Titegroup. The max load is 5 gr Titegroup and the minimum OAL is given as 1.610. Does the OAL apply to the load in general or can I set my OAL at the SAAMI OAL of 1.59 for a 4.5 gr load? Last edited by Outlaw75; August 15, 2014 at 01:54 PM.

August 15, 2014, 10:34 PM	#7
Nick_C_S Senior Member Join Date: March 21, 2013 Location: Idaho Posts: 5,524	I'll explain it: Not that it addresses the question in the original post, but if it's a 158g LSWC, chances are really good that there is a crimp groove in the bullet. You should put your calipers away and seat to that crimp groove. Most revolver bullets have a crimp groove or cannelure (in the case of jacketed). Simply seat the bullet to where the case mouth resides at the groove and crimp it. My first couple years of loading was strictly revolver rounds. I didn't even know why the starter kit I bought came with a set of calipers Nowdays, plated bullets are getting popular for revolver rounds - then it's time to bust out the calipers. Then it's also time to get a taper crimp die - but that's another post. __________________ Gun control laws benefit only criminals and politicians - but then, I repeat myself. Life Member, National Rifle Association

August 15, 2014, 07:05 PM	#2
Average Joe Senior Member Join Date: August 29, 2005 Location: Central Florida Posts: 1,325	The deeper you set the projectile, the more pressure you develop. The powder manufacture knows this, and tells you what the OAL is for your given load.

August 15, 2014, 07:50 PM	#3
Outlaw75 Member Join Date: May 7, 2014 Location: Glendale, AZ Posts: 55	Yes, thanks! I was looking at load data on Hodgdon's website and noticed that the listed the OAL for the caliber/bullet combination, regardless of the number of grains.

August 15, 2014, 08:26 PM	#4
Mobuck Junior member Join Date: February 2, 2010 Posts: 6,846	OAL is often dictated by crimp groove location.

August 15, 2014, 08:55 PM	#5
davery25 Senior Member Join Date: October 4, 2011 Location: Australia Posts: 318	It's really just an indicator. You'll just need to be aware that the further in you seat, the higher the pressure and that's going to be something to watch always but particularly at the higher ends of the charge range. For my 223 using 77 grain A-Max bullets I had to seat way deeper than the manuals OAL because they needed to fit into a Tikka T3's stock magazine. It was fine for every powder except Benchmark 2 which started to give pressure signs at the higher end