Xtreme 9mm 147 grain Hollow Point - OAL & Ogive

[3GDad]

I had some issues cycling this load at a 1.15 OAL with 3.2 grains of Titegroup out of a Glock 35 with a 40-9 KKM conversion barrel even though they passed the plunk test.  Seems the slide didn't move far enough back to provide sufficient room for the fired case to clear before the next load fed. I swapped my 17lb spring for a 13lb spring which solved the problem, but the recoil is snappier.  I am putting the original 17lb spring back in and will try a shorter OAL, thinking Ogive was the issue. Curious what OAL folks are using with Xtreme hollow points.

[Sarge]

I would run a 15 in it, or maybe a 14, or bump the charge a little.

 

 I think you're barking up the wrong tree by changing oal to fix short stroking.

[3GDad]

Thanks Sarge!

[3GDad]

I'm ordering the 15lb spring and will compare it to a slightly hotter charge with the 17lb spring, to see which I might prefer.

Separate from the cycling, I've read that it's best to use the longest OAL possible, and recognize that I must work this up based on my own G34 stock barrel and G35 with the KKM 40-9 conversion barrel, but am curious what other Glock owners might be using for OAL with the hollow point loads to get a general sense of what other Glock owners are using.  I had loads pass the plunk test at 1.15 but think it should be a shorter OAL based on Ogive .... Curious what others think.

[3GDad]

Dup

Edited August 21, 2016 by 3GDad

[3GDad]

I loaded the 147 grain 9mm hollow points with OALs at 1.10 \ 1.11 \ 1.12 \ 1.14 \ 1.145 and 1.15 and hit the range today.

3.2 grains of Titegroup with the stock 17lb Spring in my Glock 35 with a KKM 40-9 conversion barrel for 9mm loads.

All loads fed, and cycled without a problem.  I had previously had issues cycling a batch that I loaded at 1.15 OAL and thought the Ogive of the hollow point profile might have required a shorter OAL, but seems ok and I am now thinking my previous problems could have been variations in the powder drop in those earlier loads, today went well.  I will check the powder drops more often during my loading sessions to insure consisted powder charges. I'm using a Dillon XL 650.

Groups seemed pretty tight at all OALs, the longer OAL might have been a bit tighter but they were all pretty similar sized groups.

 

[Sarge]

On August 19, 2016 at 6:35 PM, 3GDad said:

I'm ordering the 15lb spring and will compare it to a slightly hotter charge with the 17lb spring, to see which I might prefer.

Separate from the cycling, I've read that it's best to use the longest OAL possible, and recognize that I must work this up based on my own G34 stock barrel and G35 with the KKM 40-9 conversion barrel, but am curious what other Glock owners might be using for OAL with the hollow point loads to get a general sense of what other Glock owners are using.  I had loads pass the plunk test at 1.15 but think it should be a shorter OAL based on Ogive .... Curious what others think.

Using longest load possible is more suited to accuracy in rifles or pistols for games that require more precision. 

This game requires accuracy but other things can be just as, or more important. 100% function, I.e. Feeding, ejection, PF consistency, etc are critical.

in my Glock 34 with MG 124 CMJ's I could easily load beyond 1.15 but found 1.13 to be the optimum length in my particular gun.

i also found the gun much preferred 124 over 147's. 

[kneelingatlas]

Did you chrono your short loads vs long loads?  Typically you make more velocity with a shorter load and the same charge.

[3GDad]

Thanks again Sarge.  All too true, I'm focused on the reliability first and accuracy second, hoping to find the right combo that Insill be comfortable with and your tips are a big help.

I had a painful stage at a match recently where I had cycling issues, accuracy doesn't matter much when your standing there burning time clearing jams and I won't soon forget that.

kneelingatlas - I just got my first chrono yesterday, a Chrono Beta Master, but haven't used it yet.  I'm very interested to see the effect of the shorter OAL on velocity, hadn't given it much thought, but sounds like I should.  Now I will be able to measure power factors at different OAL / charge combinations.

I am also planning on loading 165 grain 9mm and 200 grain 40 caliber and am concerned about the pressures with the reduced space in the case. I'm using Titegroup, might look for a slower burning powder, maybe WSF, but want to know my velocities for sure so I can work up a load safely, and glad I now have the Chono.  Wondering if QuickLOAD is the only way to measure case pressure, I'm most concerned about case pressure with the heavier loads, would probably look for the longest reliable OAL with those loads to reduce pressure. Just wish it was offered as an app for iPhone / iPad.

[judgecrater]

On 8/19/2016 at 6:35 PM, 3GDad said:

I'm ordering the 15lb spring and will compare it to a slightly hotter charge with the 17lb spring, to see which I might prefer.

Separate from the cycling, I've read that it's best to use the longest OAL possible, and recognize that I must work this up based on my own G34 stock barrel and G35 with the KKM 40-9 conversion barrel, but am curious what other Glock owners might be using for OAL with the hollow point loads to get a general sense of what other Glock owners are using.  I had loads pass the plunk test at 1.15 but think it should be a shorter OAL based on Ogive .... Curious what others think.

If it passes plunk, does not bind in the magazine and feeds 100% I don't see why shortening would be of benefit.  Am I missing anything?  How could you improve on this?

[3GDad]

I had issues cycling this load at a competition where I had loaded them at 1.15 OAL even though they passed the plunk test and was thinking I should load them at a shorter OAL due to the Ogive of the hollow point nose.  The empty case wasn't clearing before the next round would feed and would jam against the empty case as the empty was ejecting.  Seems like more of an issue with short stroking slide (light load) than the OAL. 

I purchased a 13lb Spring and they all cycled, but I didn't like the increase in snappiness of the recoil with the lighter Spring and wanted to go back to the 17lb Spring and was hoping that I would not to have to bump up the powder charge.  I believe the OAL for hollow points should be shorter than 1.15 and was curious if a shorter OAL would enable the empty case to clear before the nose of the next round feeding would catch and jam the empty case on the way out.

I went back to the range and tried several OALs. To my surprise I was able to cycle all of my 1.15 OAL loads this time with the heavier 17lb Spring and now think I may have just had some variation in the powder drop on the rounds that jammed during the competition.  Murphys Law.  Just hoping to avoid the chance of it ever happening again, it really screwed me on that stage at that time and wasn't sure if most folks load the hollow points at a shorter OAL than normal round nose profiles.

[BritinUSA]

RN bullets will seat longer, hollow point or flat point will need to be shorter because of the ogive. That same ogive will mean that the amount of space available inside the case is probably larger with the FP or HP bullets as the bullets themselves are shorter. That may lower the pressure and the PF, which could possibly lead to the slide not coming back far enough to eject the case and pick up the new round.

Secondly, I had issues recently with my XL650 where the powder measure was not throwing enough powder, the two screws on the plate that drives the powder bar has worked loose and this was causing some lower than normal PF.

[3GDad]

Thanks! That makes a lot of sense. I'm going to load them at 1.135 and will check those 2 screws.