Overall Length (OAL) & Affect on Accuracy / Reliability with Nosler 185gr JHP

Gentleman,

Looking to start loading the Magnus J187 185 GR JHP for EIC competition.  One item of confusion that I have is on the determination of OAL.  For 45 ACP 1.275" is the max OAL.  For the Nosler style bullets, the range is:  4.5 - 4.7 gr of Bullseye and OAL of 1.20 - 1.25. It seems that there is a trend toward 1.20" which is shorter than specification and I'm confused on why that would be as a novice reloader/shooter.  Understood that everything has to be tested in my pistol for proper tuning, but I didn't want to rely on trial and error and was hoping to get an understanding of the "why" behind this.   Some questions I had.


Why is the Nosler loaded to a shorter OAL than the factory ammunition? 

Does a shorter OAL increase reliability, accuracy or both?
I've seen some posts that the Nosler OAL is spec at 1.120" but what is source of this information?

Thanks,
Derek

Here are the most popular starting loads I could find:

4.5 gr of Bullseye    with  185 gr   Nosler / Zero JHP - OAL  1.195"
4.7 gr of Bullseye    with  185 gr   Nosler / Zero JHP - OAL  1.20"
4.5  gr  of  Bullseye      with    185 gr     Nosler  /  Zero  JHP  -  OAL  1.25"
4.5 gr of N310        with  185 gr   Nosler / Zero JHP - OAL  1.25"
4.6 gr of Titegroup  with  185 gr   Nosler/  Zero JHP - OAL  1.20"

Some threads that I found that were helpful:

http://smith-wessonforum.com/reloading/358237-185-jhp-bullseye-load-test-prelim.html

https://www.bullseyeforum.net/t1209-pet-loads-of-top-shooters-loads-from-the-past

https://www.bullseyeforum.net/t3876-nosler-custom-comp-45?highlight=nosler

https://www.bullseyeforum.net/t2742-nosler-185-jhp-with-n310?highlight=nosler

https://www.bullseyeforum.net/t1662-nosler-185-comp-hp-with-bullseye?highlight=nosler

https://www.bullseyeforum.net/t1347-zero-185gr-jhp-vs-nosler-185gr-jhp?highlight=nosler

1.275 is the max but the 230 fmj or hg68 200 Lswc are the only ones that get usually close to that, 1.120 is right for a 185 button nose like the Remington match but too short for the others, 1.200 is min I would do w/nosler and the zero is about 1.205-1.210 I just measured a factory Winchester 185 jhp and it was 1.206 and a factory Remington 185 jhp was 1.203, just load them like that and you will have accurate ammo.

1.20 works best for us. 230 gr FMj is the longest bullet typically loaded in a 45acp. Other bullets are shorter, adjust oal accordingly.

As always sage advice and appreciated Terry and echoes what Jerry Keefer shot me in a PM.  Thanks again for the great bullets!  The 801N were terrific and can't wait to try the J187 bullets from Magnus.  I weighed all the 801Ns and the consistency in weight and diameter from bullet to bullet was incredible.   

Cheers,
Derek

I was on the old Bullseye-L with dial-up, when I started loading the "Nosler load" back in the 90's. I got some great advice from Dave Salyer. Dave worked with Al Dorman, to develop the first "Nosler load". Later the USMC team adopted it with Dave and Al's blessings. I didn't have any Vihtavouri 310 powder available in the area where I lived. Dave advised me to just use Bullseye (4.5 grains). He said that Bullseye was pretty close to Vihtavouri in the accuracy tests they did. He also said that within reason, their tests showed that COAL didn't make a difference in accuracy. I settled on 1.215" with a taper crimp of .470" in new Starline brass. A guy at our club bumped up the load to 4.6 grains of Bullseye and got the best machine rest group I've ever seen. He was shooting a new Rock River wad gun and his group was under an inch at 50 yards.

Nosler 185, 4.8 to 5.0 WST, WLP primer, 1.24 OAL, I always use once fired Federal brass.  I own 4 wad guns and 1.625 is the largest 10 shot group and 1.1 is the smallest out of my Ransom rest at 50 yds. One of my wad guns prefers 4.8 the other 3 prefer 5.0 of the WST. I have tried many powders and always go back to WST.
Tom Ginovsky
NRA 2650 Club

In general, the longest COL is usually the most accurate.
Per Ramshot:
"SPECIAL NOTE ON CARTRIDGE OVERALL LENGTH “COL”
It is important to note that the SAAMI “COL” values are for the firearms and ammunition manufacturers industry and must be seen as a guideline only.
The individual reloader is free to adjust this dimension to suit their particular firearm-component-weapon combination.
This parameter is determined by various dimensions such as
1) magazine length (space),
2) freebore-lead dimensions of
the barrel,
3) ogive or profile of the projectile and
4) position of cannelure or crimp groove.
• Always begin loading at the minimum "Start Load".
• Increase in 2% increments towards the Maximum Load.
• Watch for signs of excessive pressure.
• Never exceed the Maximum Load."
 
Your COL (OAL) is determined by your barrel (chamber and throat dimensions) and your gun (feed ramp) and your magazine (COL that fits magazine and when the magazine lips release the round for feeding) and the PARTICULAR bullet you are using. What worked in a pressure barrel or the lab's gun or in my gun has very little to do with what will work best in your gun.
Take the barrel out of the gun. Create two inert dummy rounds (no powder or primer) at max COL and remove enough case mouth flare for rounds to chamber (you can determine this by using an empty sized case, expand and flare, and remove the flare just until the case "plunks" in the barrel).
Drop the inert rounds in and decrease the COL until they chamber completely. This will be your "max" effective COL.
You can also do this for any chambering problems you have. Remove the barrel and drop rounds in until you find one that won't chamber. Take that round and "paint" the bullet and case black with Magic Marker or other marker. Drop round in barrel (or gage) and rotate it back-and-forth.
Remove and inspect the round:
1) scratches on bullet--COL is too long
2) scratches on edge of the case mouth--insufficient crimp
3) scratches just below the case mouth--too much crimp, you're crushing the case
4) scratches on case at base of bullet--bullet seated crooked due to insufficient case expansion (not case mouth flare) or improper seating stem fit

5) scratches on case just above extractor groove--case bulge not removed during sizing. May need a bulge buster.

Great post, but I may need to find a video on determing the COL/OAL that is the maximum for my pistol or hit up some of the USNMST gray beard guys to show me before I goon something up.  Reloading over several weeks with an experienced reloader/bullseye shooter has been a great help in getting started.  Lots to learn!

What barrel do you have? is it stock or other like kart? The 1.200-1.210 is tried and true for accuracy and most important FUNTION!  Loading as long as possible may be slightly more accurate( but it has not proven that in many tests) it can often cause feeding issues too, but for pure speculation lets say it could, ask any good shooter and they will tell you function trumps a little extra accuracy any day. If it functions every round you have no alibies and that is much more likely to be get a better score. Besides, these nosler and zero 185 jhp loads shoot  2'' most times out of a match barrel, even if you could gain a a 1/2'' at 50 yards, only 1% of shooters could take advantage of it. Stop overthinking this and load up some and go practice!

DavidR wrote:What barrel do you have? is it stock or other like kart?
The 1.200-1.210 is tried and true for accuracy and most important FUNTION! 
Stop overthinking this and load up some and go practice!

Stock Range Officer, stock barrel. 
In May/June my ball gun should be done, hopefully in time for Interservice, but fingers crossed! 

Right On!  I reloaded 300 rounds of 1.205 COL/OAL with 4.5 gr of Bullseye.  I'll shoot these Monday night in the weekly league to make sure everything functions well.

Loads will be for the Fleet/All Navy matches next week at Quantico.  I can tune the recipe up before interservice when I have my ball gun, which does have a Kart barrel.

JayhawkNavy02 wrote:

DavidR wrote:What barrel do you have? is it stock or other like kart?
The 1.200-1.210 is tried and true for accuracy and most important FUNTION! 
Stop overthinking this and load up some and go practice!

Stock Range Officer, but here in May/June my hardball gun should be done, hopefully in time for Interservice, but fingers are crossed!  Loads will be for the Fleet/All Navy matches next week.

Right On!  I reloaded 300 rounds of 1.205 COL/OAL with 4.5 gr of Bullseye.  I'll shoot these Monday night in the weekly league to make sure everything functions well.

You should be good to go.
My loads are between 1.20"-1.210" with 4.6gr +/- of BE powder.

Clarence

Out of curiosity what recoil spring are you running with that setup?

JayhawkNavy02 wrote:Out of curiosity what recoil spring are you running with that setup?

It is a Clark Sr. heavy long slide with a 1" Ultradot using Leupold PRW rings on an aluminum slide mount.
16# recoil spring.

Clarence

I run a 11 with a slide mount and 1'' ud on mine but iron sight RO id go with a 14 or 15.

Roger.  I have a 13 and 16 spring.  Ordered a 14 and 15 Wolff variable to see what cycles.

FWIW Roddy made Nosler loads measure 1.200-1.203 depending on what nose booger you hit on the bullet.
 And crimp is .465

Jack H wrote:FWIW Roddy made Nosler loads measure 1.200-1.203 depending on what nose booger you hit on the bullet.
 And crimp is .465

I had a discussion with him about the very heavy crimp he uses. I did some tests. With my loading equipment and pistol, the heavier the crimp the less accuracy. I did the tests out of a machine rest at 50 yards with the Nosler bullet. I recommend that one start with something like a .470" taper crimp.

Function tested 20 rounds of 4.6BE, 1.23 OAL and .470 crimp this afternoon in my borrowed unknown source ball gun. It worked the stock spring just fine in slow fire and rapid.

Stock spring?  Is yours 15lb or 16lb?

16 supposedly. we tested it on the spring tester 3 years ago and that's what it was then. It doesn't get shot much but it locks up tight and there is no side to side movement. It's an old Series 70, that someone made into a ball gun back in the 70's or 80's.

BE Mike wrote:

Jack H wrote:FWIW Roddy made Nosler loads measure 1.200-1.203 depending on what nose booger you hit on the bullet.
 And crimp is .465

I had a discussion with him about the very heavy crimp he uses. I did some tests. With my loading equipment and pistol, the heavier the crimp the less accuracy. I did the tests out of a machine rest at 50 yards with the Nosler bullet. I recommend that one start with something like a .470" taper crimp.

The round I measured is from the same batch Roddy loaded and used to test my HB gun.  I use it as my set-up standard. 
The HB gun test target (with the Noslers) is 1" for nine shots 1&1/16 for 10.  Roddy is presently converting the HB gun to wad.  Just the hammer, beavertail, sight rail, and trigger weight.

Add that my caliper is a Starrett set with a 1" standard, and at zero it reads zero.  BTW a cheap digital I have will seldom agree with the Starrett.

Jack,

What is the best way to measure crimp accurately?

Derek

Derek
I look through a light with a built in magnifier to accurately place the caliper jaws as close to the edge of the case mouth as possible.  In fact I place the caliper jaws thin part half on and half off the brass.

Roger,

Thanks Jack.

hand pressure has a lot to do with what you get too, some guys can gauge a .470 and get .468, its hard to know how they got what they claim.