Switching from 45acp LSWC to LRN

Roland Thunder · January 30, 2016, 09:05 AM

I have been using 45acp 200 gr LSWC in my 1911 for several years. I recently bought some 200 gr LRN. I switched because my new gun, Sig 320 FS doesn't feed the LSWC's very well although my Colt 1911 does just fine with them.

The LRN bullets are about .02 shorter than the LSWC's. Should I load the LRNs with a OAL .02 shorter to achieve the same pressure.

I have been using 4.1 gr Bulle Eye Powder

Kevin Rohrer · January 30, 2016, 09:34 AM

I'd load them to the same OAL, as long as that length reliably feeds

Metal god · January 30, 2016, 11:52 AM

No expert here , The one thing I'd do is seat one of each then mark at case mouth . Pull them both and compare how much bullet is being seated in the case . The 45 is a big low pressure case . A few thousandths difference should not make a substantial difference in pressure .

noylj · January 30, 2016, 06:59 PM

Who started the idea that loading to same seating depth would give the same pressure? What about bearing surface and distance to lede/rifling? Is accuracy of any importance? First, the round must feed and chamber.
Try establishing COL for each bullet and ignore seating depth.
Determine COL with a couple of inert dummy rounds.
I know that some don't want to change their load and they want the same PF, but then, why change bullet? Also, don't these folks have chronographs any way?
Always assume a new bullet means a new load work-up.

g.willikers · January 31, 2016, 01:54 PM

The RNL bullet will probably work better if the rounds are loaded to the same OAL as good ole' factory FMJ ammo.
Then work up the load accordingly.

While a chronograph is indeed a welcome addition to reloading, how did we ever get along without them.
We did, though.
Had to, they didn't become commonly available until fairly recently in the history of reloading.
Serious shooters might make their own chronographs, but mostly we just trusted the loading manuals and seat of the pants testing.
Seemed to work out ok.

T. O'Heir · January 31, 2016, 03:16 PM

LRN bullets are about .02 shorter because they're not flat. OAL for an RN is 1.200", but I wouldn't worry about 20 thou too much. The .45 is a forgiving fellow.

January 30, 2016, 09:05 AM	#1
Roland Thunder Senior Member Join Date: December 29, 2010 Location: Gwinnett County Georgia Posts: 1,136	Switching from 45acp LSWC to LRN I have been using 45acp 200 gr LSWC in my 1911 for several years. I recently bought some 200 gr LRN. I switched because my new gun, Sig 320 FS doesn't feed the LSWC's very well although my Colt 1911 does just fine with them. The LRN bullets are about .02 shorter than the LSWC's. Should I load the LRNs with a OAL .02 shorter to achieve the same pressure. I have been using 4.1 gr Bulle Eye Powder __________________ Do not follow where the path may lead, go, instead where there is no path and leave a trail - Ralph Waldo Emerson

January 30, 2016, 09:34 AM	#2
Kevin Rohrer Senior Member Join Date: May 19, 2010 Location: Medina, Ohio Posts: 1,049	I'd load them to the same OAL, as long as that length reliably feeds __________________ Member: Orange Gunsite Family, NRA--Life, ARTCA, and American Legion. Caveat Emptor: Cavery Grips/AmericanGripz/Prestige Grips/Stealth Grips from Clayton, NC. He is a scammer

January 30, 2016, 11:52 AM	#3
Metal god Senior Member Join Date: April 10, 2012 Location: San Diego CA Posts: 6,876	No expert here , The one thing I'd do is seat one of each then mark at case mouth . Pull them both and compare how much bullet is being seated in the case . The 45 is a big low pressure case . A few thousandths difference should not make a substantial difference in pressure . __________________ If Jesus had a gun , he'd probably still be alive ! I almost always write my posts regardless of content in a jovial manor and intent . If that's not how you took it , please try again .

January 31, 2016, 01:54 PM	#5
g.willikers Senior Member Join Date: September 28, 2008 Posts: 10,442	The RNL bullet will probably work better if the rounds are loaded to the same OAL as good ole' factory FMJ ammo. Then work up the load accordingly. While a chronograph is indeed a welcome addition to reloading, how did we ever get along without them. We did, though. Had to, they didn't become commonly available until fairly recently in the history of reloading. Serious shooters might make their own chronographs, but mostly we just trusted the loading manuals and seat of the pants testing. Seemed to work out ok. __________________ Walt Kelly, alias Pogo, sez: “Don't take life so serious, son, it ain't nohow permanent.” Last edited by g.willikers; January 31, 2016 at 02:05 PM.

January 31, 2016, 03:16 PM	#6
T. O'Heir Senior Member Join Date: February 13, 2002 Location: Canada Posts: 12,453	LRN bullets are about .02 shorter because they're not flat. OAL for an RN is 1.200", but I wouldn't worry about 20 thou too much. The .45 is a forgiving fellow. __________________ Spelling and grammar count!

January 30, 2016, 06:59 PM	#4
noylj Senior Member Join Date: October 21, 2007 Location: Between CA and NM Posts: 858	Who started the idea that loading to same seating depth would give the same pressure? What about bearing surface and distance to lede/rifling? Is accuracy of any importance? First, the round must feed and chamber. Try establishing COL for each bullet and ignore seating depth. Determine COL with a couple of inert dummy rounds. I know that some don't want to change their load and they want the same PF, but then, why change bullet? Also, don't these folks have chronographs any way? Always assume a new bullet means a new load work-up.