roklock Posted September 17, 2015 Share Posted September 17, 2015 How do you determine where you want your OAL for 9 major loads? Just got a trubor where the previous owner was loading 124 MG JHP at 1.175 (1000 rounds) but when doing the search function most seem to be choosing 1.160-1.170 I have done long range load work ups where you try different seating depths after finding a node, are you actually doing this when working up loads for our sport? Or do you arbitrarily just pick one and work up loads for it? Thanks, Steve Link to comment Share on other sites More sharing options...
GrumpyOne Posted September 18, 2015 Share Posted September 18, 2015 Use the barrel of your gun to find the OAL. Link to comment Share on other sites More sharing options...
Sarge Posted September 18, 2015 Share Posted September 18, 2015 Not much difference in 70 and 75 in the grand scheme of things though over 1.17 seems a bit long. I know guys that load to 1.15 in SV's so basically whatever works best is the way to go. I like staying under 1.17 because I use 115's and they are barely in there if I stretch them out too much. Load several at different lengths with different charges and find the one that runs100% and gives the best on target performance and gets you the PF and gas you need Link to comment Share on other sites More sharing options...
roklock Posted September 18, 2015 Author Share Posted September 18, 2015 Ok, I get it now...forgot about bullets being longer the heavier they get Link to comment Share on other sites More sharing options...
al503 Posted September 18, 2015 Share Posted September 18, 2015 Bullet length, your barrel's freebore, and whether you're running spacers in your mags or not, are going to be the big factors. If you're running spacers in your mag, I'd start at something around 1.165" If you're not running spacers, I'd start at 1.2" Load a couple of dummy rounds at those lengths and see if they'll pass the plunk test in your barrel. Reduce the OAL until it does. Make sure the barrel is clean with no fouling. Once you have that length, load up the round in a mag and slingshot it into the chamber a few times. If the OAL doesn't shorten more than .001", you're good to go. I run 124 MG JHPs at 1.2" if the load is not compressed (AA#7 and SP2) and 1.21" if it is compressed (3n38, n105). I've found that there is enough bearing surface to prevent bullet setback even with repeated chamberings. Setback is less of a concern if you're running a compressed load, for obvious reasons. The longer the OAL, the lower the initial pressure spike, which is important for 9 major. Link to comment Share on other sites More sharing options...
igolfat8 Posted September 18, 2015 Share Posted September 18, 2015 (edited) Use the barrel of your gun to find the OAL. +1 For what Grumpy said. What sense does it make to base COAL off of what your magazine will accept if your barrel won't accept it. If your COAL is too long and your bullet seats against the rifling your gun will never go into battery unless you force it closed, which is not a good habit to get into. Edited September 18, 2015 by igolfat8 Link to comment Share on other sites More sharing options...
Sarge Posted September 18, 2015 Share Posted September 18, 2015 Use the barrel of your gun to find the OAL. +1 For what Grumpy said. . I agree if you are looking for MAX oal. Finding the BEST oal is still trial and error. Link to comment Share on other sites More sharing options...
roklock Posted September 18, 2015 Author Share Posted September 18, 2015 Thanks everyone...fully understand how to find max OAL but the bullet length is what I completely forgot about (never had a point where I ran out of bullet length before) Original owner was loading MG 124 JHP to 1.175, since I am going to try the 115's I think I am going to start at the 1.165 per Sarge's comment about running out of bullet length. Link to comment Share on other sites More sharing options...
echotango Posted September 18, 2015 Share Posted September 18, 2015 I run my 115 MG at 1.165 and use mag spacers. Link to comment Share on other sites More sharing options...
roklock Posted September 18, 2015 Author Share Posted September 18, 2015 I will have to check if I have spacers...will .010 shorter be enough of a difference to matter? Link to comment Share on other sites More sharing options...
Sarge Posted September 18, 2015 Share Posted September 18, 2015 I will have to check if I have spacers...will .010 shorter be enough of a difference to matter?Matter how? Link to comment Share on other sites More sharing options...
Hi-Power Jack Posted September 18, 2015 Share Posted September 18, 2015 Might also depend on which powder you're using - if you use WAC, you can shorten it up to 1.15 or 1.16", because you're using only about 7 grains. If you use slower powders, you may be near 10 grains, and need to seat the bullet out further to make room for the powder. Link to comment Share on other sites More sharing options...
roklock Posted September 18, 2015 Author Share Posted September 18, 2015 I will have to check if I have spacers...will .010 shorter be enough of a difference to matter?Matter how? I don't know yet if my mags have spacers (check tomorrow) but if they don't and he was loading to 1.175 with no issues will shooting 1.165 mean I need to get spacers? Link to comment Share on other sites More sharing options...
Steve RA Posted September 18, 2015 Share Posted September 18, 2015 No, not usually. Link to comment Share on other sites More sharing options...
shotgunone Posted September 18, 2015 Share Posted September 18, 2015 (edited) Are you all modifying your chambers? I have a new STI Trubor. I was doing the plunk test using 124 gr delta precision HP. The longest I can load is 1.130 or the bullet gets into the rifling and the case sticks out pass the hood on the barrel. Not sure what effect loading that short will have on the velocity and pressure. Thanks Edited September 18, 2015 by shotgunone Link to comment Share on other sites More sharing options...
Hi-Power Jack Posted September 19, 2015 Share Posted September 19, 2015 The longest I can load is 1.130 or the bullet gets into the rifling I'd be surprised that you can't load longer than 1.13. There are other reasons for failing the Plunk Test - like too much crimp. I'd be cautious with such a short load - might be okay with WAC (I've loaded that as low as 1.145"), but other powders take up more room). Link to comment Share on other sites More sharing options...
warpspeed Posted September 19, 2015 Share Posted September 19, 2015 The longest I can load is 1.130 or the bullet gets into the rifling and the case sticks out pass the hood on the barrel. Sounds like the bullet profile might be an issue. Link to comment Share on other sites More sharing options...
Steve RA Posted September 19, 2015 Share Posted September 19, 2015 Get the barrel throated. Link to comment Share on other sites More sharing options...
Absocold Posted September 19, 2015 Share Posted September 19, 2015 Use layout fluid on the bullet to see how far out you can go before it touches the lands. Plunk test just isn't exact enough for me. Not at 9 major pressures. Link to comment Share on other sites More sharing options...
Sarge Posted September 19, 2015 Share Posted September 19, 2015 Are you all modifying your chambers? I have a new STI Trubor. I was doing the plunk test using 124 gr delta precision HP. The longest I can load is 1.130 or the bullet gets into the rifling and the case sticks out pass the hood on the barrel. Not sure what effect loading that short will have on the velocity and pressure. Thanks That seems too short for that bullet and chamber. Make sure your crimp is right first. Link to comment Share on other sites More sharing options...
shotgunone Posted September 20, 2015 Share Posted September 20, 2015 (edited) Sorry Roklock I didn't intend to highjack your OP. The longest I can load is 1.130 or the bullet gets into the rifling and the case sticks out pass the hood on the barrel. Sounds like the bullet profile might be an issue. I have the same issue of no more than 1.130 with xtreme HP or FP in 124 gr. I can get to about 1.150 with xtreme 124 gr RN. Get the barrel throated. When you talk about throating the barrel what exactly are you referring too? In shotguns we cut the forcing cones in front of the chamber to reduce recoil and improve patterning. Is this the kind of throating your are talking about by tapering the rifling in front of the chamber? Use layout fluid on the bullet to see how far out you can go before it touches the lands. Plunk test just isn't exact enough for me. Not at 9 major pressures. I haven't used layout fluid but I did resize an unprimed case and start a bullet in it and pressed it into the chamber all the way. I removed the cartridge and measured it. I don't recall the exact number but I know it was below the 1.160+ that most people load 9 major too. On the RN xtremes it seems like it was about 1.155 or maybe a couple 0.001 more. I know that loading the delta precision 124gr HP at 1.135 to 1.140 will cause the case to not fit in the chamber flush with the back of the hood on the barrel. Are you all modifying your chambers? I have a new STI Trubor. I was doing the plunk test using 124 gr delta precision HP. The longest I can load is 1.130 or the bullet gets into the rifling and the case sticks out pass the hood on the barrel.Not sure what effect loading that short will have on the velocity and pressure.ThanksThat seems too short for that bullet and chamber. Make sure your crimp is right first. Hi-Power Jack and Sarge: I know your not suppose to use a lot of crimp on auto pistol cartridges because you can buckle the case and cause issues. But how much crimp is to much. On plated bullets i have my crimp set where it will just leave a slight indent in the plating as it removes the bell from the case mouth. On the DP HP it doesn't leave any mark that I can see on pulled bullets except for some scuffing where the bullet is pulled from the case. Again sorry for highjacking the thread but I do appreciate any help with this. Thanks Edited September 20, 2015 by shotgunone Link to comment Share on other sites More sharing options...
Sarge Posted September 20, 2015 Share Posted September 20, 2015 Yes throating the barrel is just forward of the chamber to make more room for a bullet. Takes a few seconds and cost about $40 if you send it to Matt Cheely. He'll send it back in a few days as well Link to comment Share on other sites More sharing options...
Sarge Posted September 20, 2015 Share Posted September 20, 2015 Sorry Roklock I didn't intend to highjack your OP. The longest I can load is 1.130 or the bullet gets into the rifling and the case sticks out pass the hood on the barrel. Sounds like the bullet profile might be an issue. I have the same issue of no more than 1.130 with xtreme HP or FP in 124 gr. I can get to about 1.150 with xtreme 124 gr RN. Get the barrel throated. When you talk about throating the barrel what exactly are you referring too? In shotguns we cut the forcing cones in front of the chamber to reduce recoil and improve patterning. Is this the kind of throating your are talking about by tapering the rifling in front of the chamber? Use layout fluid on the bullet to see how far out you can go before it touches the lands. Plunk test just isn't exact enough for me. Not at 9 major pressures. I haven't used layout fluid but I did resize an unprimed case and start a bullet in it and pressed it into the chamber all the way. I removed the cartridge and measured it. I don't recall the exact number but I know it was below the 1.160+ that most people load 9 major too. On the RN xtremes it seems like it was about 1.155 or maybe a couple 0.001 more. I know that loading the delta precision 124gr HP at 1.135 to 1.140 will cause the case to not fit in the chamber flush with the back of the hood on the barrel. Are you all modifying your chambers? I have a new STI Trubor. I was doing the plunk test using 124 gr delta precision HP. The longest I can load is 1.130 or the bullet gets into the rifling and the case sticks out pass the hood on the barrel. Not sure what effect loading that short will have on the velocity and pressure. Thanks That seems too short for that bullet and chamber. Make sure your crimp is right first. Hi-Power Jack and Sarge: I know your not suppose to use a lot of crimp on auto pistol cartridges because you can buckle the case and cause issues. But how much crimp is to much. On plated bullets i have my crimp set where it will just leave a slight indent in the plating as it removes the bell from the case mouth. On the DP HP it doesn't leave any mark that I can see on pulled bullets except for some scuffing where the bullet is pulled from the case. Again sorry for highjacking the thread but I do appreciate any help with this. Thanks Hmm.. Perhaps try a tad more crimp. The barrel may just be bad and need throated. I run MG JHP and they have very long straight sides. I can stretch them out to 1.17+ Link to comment Share on other sites More sharing options...
Eric_Vmax Posted October 18, 2015 Share Posted October 18, 2015 Great information guys. Glad I read this. Sent from my SCH-I545 using Tapatalk Link to comment Share on other sites More sharing options...
open17 Posted November 12, 2015 Share Posted November 12, 2015 Currently running Precision Delta 115 and 124 JHP's at 1.175 . Schuemann Ultimatch 9mm barrel. I throated it to plunk a 1.200 test round. New version MBX mags, no spacer. Running a EGW U sizer---seems to hold even the 115's just fine. Link to comment Share on other sites More sharing options...
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