Is loading as long as possible really best?

[EngineerEli]

Hey all,

I I have been reloading for quite a few years now, but I find myself unsure how to proceed. I had been finishing up some old bullets, I had to load very short for, before switching back to the ones I most prefer, basically these (http://www.bayoubullets.net/9mm-124-gr-rn-500-ct/). I used to load these bullets to 1.140" but was was surprised last night to see I could actually load them out to 1.165" and pass the plunk test. They also fit into the mags at that length. I feel like I have heard you want to go as long as you can or have something like a 0.005"-0.010" gap between the bullet and the lands for the best accuracy, but this seems excessive for my minor production loads. I also know the longer you load the more powder is required to make the same PF, which would technically make more gas and more recoil. I previously loaded 4.0 gr of WST which is a pretty fast powder for 9mm, so maybe a bit more case volume (longer OAL) could be a good insurance policy. The gun is a Tanfo Stock II BTW...

So how should I determine the length to load the ammo, to maximize accuracy, and minimize recoil (and powder consumption I suppose)?

-Eli

[Steve RA]

Sometimes !!!

Load some as long as will pass the plunk test and fit in the magazine and try them. Then, shorten them 10 or 15 thousandths and do that a couple of times and see which length is most accurate for you. Don't go extremely short and if you shoot competition, make sure the load you settle on makes whatever PF you need.

[cnote]

I look simply for the accuracy in minor loads, and the oal that plunks, fits the mags and functions consistently, while comfortably making PF is the winner. Different story with .40 major loads and heavy bullets.

You don't want to damage that 5.4

Edited December 23, 2015 by cnote

[Miranda]

things I have read and I have not been able to test.

longest OAL is to help accuracy.

the why was explained as the bullet does not get to jump to the rifling

the other was that for reaching major power factor one loaded long

with the reason that you had more room for powder AND more volume

to help keep peak pressure down.

I do not think the two are directly related...( I have not read they are anyway)

that is to say longer oal AND more powder will get more accuracy.

and last item here is that the crown of the barrel is more important

for accuracy than OAL.

short of screwing a bi-pod to my pistol....

I am not sure how I'd test the ideas above.

[Steve RA]

You could get a Ransom rest.

[LilBunniFuFu]

short of screwing a bi-pod to my pistol....

I am not sure how I'd test the ideas above.

Find some one with a ransom rest or if you can do a consistent sandbag test.

[dapribek]

What is the plunk test?

[Hi-Power Jack]

What is the plunk test?

Aha!! Makes me feel a little better that I'm NOT the only

one who doesn't know how to do a search.

Drop round into chamber so that it's fully seated (PLUNK),

and then make sure it spins freely and drops freely.

If it doesn't, it's probably too long.

[LilBunniFuFu]

And that can cause a bunch of problems in it self.

[Sarge]

My minor loads are much more accurate when I keep them well short of max but my 9MAJOR loads are the opposite.

[superdude]

What is the plunk test?

http://www.shootingtimes.com/reloading/reloading-tips-the-plunk-test/

[jtaylor996]

Still looking for that mythical buddy that has a ransom rest and is willing to loan it out...

[CZinSC]

Depends on the gun, the bullet, the powder, etc, etc. in other words, you need to test all variables. Find out how long you can load, pick a max OAL, then load some up, then step down in .005" increments. find the most accurate. The PF at longest may be lower than the shortest you load. So after all your accuracy test, you should chrono to make sure you still make PF. If not, you might have to bump up the charge. if you do, this may affect accuracy, so you will have to test that again.

When i was shooting an SP01 in Production, everyone swore by short loads. Said they were the best. Never saw anyone say they actually did some sort of scientific testing. Everyone was just using what they saw online. I was loading 1.150 because i found that to be the most accurate after numerous tests on a ransom.

So basically, test your gun, because even the same make, model, etc can be slightly different from one to another.

[jmorris]

I load all of my minor 147's to 1.160", any longer and they have problems out of some mags.

Edited December 23, 2015 by jmorris

[lcs]

I start out with the max the mags will accept. I then start testing for accuracy. I will try different OAL and see what kind of groups I get.

Every barrel is different.

[jcc7x7]

Longer OAL often helps with how the gun feeds

I mostly shoot 1911/2011's and find in 9mm, 40S&W that the longer I can load the smoother the gun runs.

Most all of my guns will feed short ammo reliably BUT there is a chur chunk as its loading

With longer ammo the feeding is smoother and obviously reliable so I want the smoothness

[Grump]

Go too long and the casemouth can't grip the bullet properly during feeding.

Don't remember how long I went, but with Hornady XTPs I was still not touching the lands or the leade by the time the bullets were getting cocked on feeding and accuracy went to 4 inches or worse at 25 yards. That was a LONG time ago, and now that I think of it, a different gun (two actually, both no longer here).

Short of that point of being overly long, I never detected an accuracy difference from loading longer or shorter, from 1.05" out to 1.19". That includes a lot of testing the past two years chasing "9mm Hardball" loads for EIC competitions that I did not wind up shooting in. Doing reality checks with JHPs showed that my results with FMJs (Hornady and Sierra) were just not panning out.

[texasref]

Eli,

I assume that you'll be using these rounds in competition.

So my Answer would be, just how accurate do you need to be when shooting stages? I've found that any rounds I reloaded were accurate enough. Any misses were due to the Indian not the arrow.

I think the better approach would be to make sure you make PF and they cycle reliably.

[EngineerEli]

I greatly appreciate all the responses!

I think what I am really trying to get at though is that I was using 4.0 gr of wst at 1.140" previously, and it seemed to do just fine. This was a few years back, and actually with a different stock II that I have since sold. But now, as I was playing around with my load I found I could load it much longer, out to 1.165". So my question really is, if I end up trying to load longer (and see if accuracy changes/improves) am I going to feel or notice the difference in recoil or sight lift of the potential extra tenth of a grain of powder I would have to use to maintain the same power factor? And, could there be any other concerns I am not thinking of when loading minor PF production ammo long? (~1.160")

I think what I really need to do is load 10 or 20 each of 1.140", 1.150", and 1.160", and maybe each at 4.0, 4.1, and 4.2 gr of WST, then test them all for accuracy and feel/recoil.

BTW - I'm a mid to high level B class shooter, and think I should be able to notice, and benefit from these slight differences, It may all be in my head though, lol.

[adamge]

Eli, I've tried playing with OAL on my 9mm reloads. I certainly didn't feel a difference in recoil. I was trying to obtain more accuracy, but I didn't find any improvements.

[RippinSVT]

To those who may doubt the effect of OAL on 9mm accuracy, I did the grand-pubah of 9mm accuracy tests last spring before Bianchi Cup, testing different brass, bullets, powders, primers, and OAL. By the end of it all I was able to get a factory G34 to shoot 6 shots into 2.6" at 50 yards from a bag. OAL made a huge difference in that test, as much as 4" group-size difference at 50. I have since used that magic load in 3 other guns with great success, as good as 1.4" at 50 for 6 shots, however I did tweek OAL for each barrel leade.

As for the Ransom, I have one I never use. I just shoot prone or benched.

[Southpaw]

To those who may doubt the effect of OAL on 9mm accuracy, I did the grand-pubah of 9mm accuracy tests last spring before Bianchi Cup, testing different brass, bullets, powders, primers, and OAL. By the end of it all I was able to get a factory G34 to shoot 6 shots into 2.6" at 50 yards from a bag. OAL made a huge difference in that test, as much as 4" group-size difference at 50. I have since used that magic load in 3 other guns with great success, as good as 1.4" at 50 for 6 shots, however I did tweek OAL for each barrel leade.

As for the Ransom, I have one I never use. I just shoot prone or benched.

So, what is this magic load???

I'd also be very interested in hearing the rest of the results from you testing with different bullets, powders, OAL, etc.

[RippinSVT]

To those who may doubt the effect of OAL on 9mm accuracy, I did the grand-pubah of 9mm accuracy tests last spring before Bianchi Cup, testing different brass, bullets, powders, primers, and OAL. By the end of it all I was able to get a factory G34 to shoot 6 shots into 2.6" at 50 yards from a bag. OAL made a huge difference in that test, as much as 4" group-size difference at 50. I have since used that magic load in 3 other guns with great success, as good as 1.4" at 50 for 6 shots, however I did tweek OAL for each barrel leade.

As for the Ransom, I have one I never use. I just shoot prone or benched.

So, what is this magic load???

I'd also be very interested in hearing the rest of the results from you testing with different bullets, powders, OAL, etc.

(134PF minor load)

-Matched 9mm cases from Speer or Lapua preferred, others work ok too, but they must match to shoot consistently. I use Lapua for major matches and buy on clearance when it's $12/100 (NOT $32/100)

-3.7gr of Titegroup...I stuck to common domestic powders as I didn't want a load for a powder I couldn't get regularly.

-115gr XTP/HAP, though Sierra Sportsmasters, Zeros, etc work well

-Federal SPP

-1.14" seems to be a happy OAL in most guns with that bullet. Short chambers won't take it and you'll have to shorten the length.

-consistent light taper crimp. Just enough to remove bell and add a smidgen of extra tension without any bullet deformation.

A few things were obvious during accuracy testing.

-Light and heavy loads shot well. Compromise loads were only so-so (140-155PF)

-Conical bullets, like XTP's, shot by FAR the best, though RN's and truncated can do ok

-Fast dense powders ruled for minor loads...TG, Bullseye, etc. I would have tested VV powders but I wanted to stay common/domestic. HS6, PP, etc were not winners for accuracy.

-Cases must match and crimp must be consistent and just right. Small cases and small variations=large extreme spreads. Rem primer pockets were loose and inconsistent, Winchester case rims were inconsistent and thus headspace was inconsistent. Speer was by far the best of the common "range brass", with Fed close behind.

-Fed SPP's gave reliable ignition and low ES/SD. Winchesters did well too, and CCI's were good but sensitive to primer pocket variations and compromised reliability (hard cup). Remingtons were similar to the Winchesters. All can work fine, but the Feds always go bang. I may do some testing with SPP Magnums since I've got 3000 collecting dust.

-After you've done a little bench testing for powder charge, then do an OAL test with 5 shot groups at 50 yards from 1.070" to 1.160" in .005" increments. You'll be amazed when you find a sweetspot.

None of this matters for steel, USPSA, IDPA, etc, but if you're a paper-puncher, AP shooter, Bullseye shooter, or PPC shooter, it makes a world of difference. I had one horrible event at Bianchi this year when my glasses fogged in the rain, so my scores didn't reflect, but this load method helped me pick up points at the long lines. I went on to use this load to place highly in a few Regionals since then, and my subsequent X-count was as high as the guy who won 4th at Bianchi, despite my overall score being equivalent to what 10-12th place shot at Bianchi. I'm talking about a Metallic sight gun where the X's don't come as easy as my Open rig. I think my last match was 1817/1920-114X, when most scores in that range yield 80-100X. All I know is that when I flub a shot that's a borderline 8-ring, I don't need the load working against me to help it into the lower scoring ring.

Cheers.

[Southpaw]

Very interesting. Thanks for sharing! I wish I could shoot accurately enough to test groups like that at 50 yards .

I'm curious, just how bad did some of the less accurate loads get? Still more than acceptable for USPSA type shooting or were some just horribly inaccurate?

Did you only test jacketed bullets or also any coated lead or plated?

[RippinSVT]

Very interesting. Thanks for sharing! I wish I could shoot accurately enough to test groups like that at 50 yards .

I'm curious, just how bad did some of the less accurate loads get? Still more than acceptable for USPSA type shooting or were some just horribly inaccurate?

Did you only test jacketed bullets or also any coated lead or plated?

Plated bullets were shit accuracy, coated were pretty good, and lead shot well when the bore was clean. "Bad" groups were around 6" at 50 for the better bullets, and 12" for plated. Still easily good enough for a 15 yard USPSA shot, just not for the high accuracy game.