ZombieHunter Posted October 19, 2012 Share Posted October 19, 2012 (edited) I'm recently experimenting with some N340 and 124 gr FMJ pills. I had loaded up few rounds at 5.6 grains based on VV load data.. but then noticed there are two different loadings, one for FMJ-RN and then another for FMJ-FP. The RN loading is quite a bit lower than the FP loading, topping out at 5.1 grains. All I can think of is because of bearing surface on the bullet.. but was curious if anyone else has loaded standard FMJ-RN bullets (Precision Delta in my case) around this same charge of 5.6 gr or there abouts? I'm initially trying to achieve 1200fps, but obviously didn't want to interpret the data incorrectly. Edited October 19, 2012 by ZombieHunter Link to comment Share on other sites More sharing options...
PingJockey Posted October 19, 2012 Share Posted October 19, 2012 The VV data that I'm looking at shows 4.5 - 5.1 N340 for a 124 gr lapua fmj rn, 4.7 - 5.1 N340 for a Rainer RN. I haven't used PD, but if that is a plated bullet, I would prolly use the data for the Rainer lead. Link to comment Share on other sites More sharing options...
ZombieHunter Posted October 19, 2012 Author Share Posted October 19, 2012 (edited) Here is the data: http://www.lapua.com/en/products/reloading/vihtavuori-reloading-data/relodata/6/34 And, no it's not a plated bullet, it's FMJ. Sorry, I meant 5.1, not 4.8... I corrected my post. Edited October 19, 2012 by ZombieHunter Link to comment Share on other sites More sharing options...
barrybrice Posted October 19, 2012 Share Posted October 19, 2012 Save yourself a lot of headache and spend a $100 on a chronograph so you can do your on custom loading/research. I broke down and did that this summer and wish I had done so a year ago. It will give you reassurance of a safe load also. Good luck. Link to comment Share on other sites More sharing options...
PingJockey Posted October 19, 2012 Share Posted October 19, 2012 I would use the Load data for the Hornady 124 gr FMJ/FP. I used that same data for a 124 gr. MG FMJ/CMJ using 4.2 N320 for a soft load. It ought to work just fine using the 124 PD and N340, if you start on the low side (5.3), and work up, using a chrony. As for the reason that the data is so much different for the Hornady FMJ and the Lapua FMJ, I really don't know, but if you look through the VV data, you will see that many of the loads using Lapua bullets are quite a bit lower than the others, of the same bullet type. Link to comment Share on other sites More sharing options...
DougCarden Posted October 19, 2012 Share Posted October 19, 2012 Due to how the bullets fit into the chamber, the FP will get pushed farther into the case, hence the OAL will be shorter and the load will need less powder to go the same speed at the FMJ with the longer rounded Ogive, which will fit into most if not all chambers at longer OAL than the FP....phew.... Hope that makes sense.... Good luck, and yes Buy a chrono as soon as you can... DougC Link to comment Share on other sites More sharing options...
ZombieHunter Posted October 19, 2012 Author Share Posted October 19, 2012 Already got one, thanks. I'm more interested in the large variance in data and the concerns of most loads I'm seeing not hitting that high (at least in the minor power factor). I'm not a newbie at this and was interested if others had loads to that weight, since the majority of what I'm seeing are bunny fart loads used in competition that just make PF. Don't worry, I'll be using a chrono to refine my loads, but that's not my question here. Link to comment Share on other sites More sharing options...
DougCarden Posted October 19, 2012 Share Posted October 19, 2012 Ok, I guess I didn't understand your question. The FP has less internal case volume since it is pushed deeper into the case, so it needs less powder for a given velocity vs. the Round nose bullet not as deep in the case. The RN needs more powder due to more internal volume to make the same PF. This will account for the difference in powder charge. Remember that VV data is a guide for the end user. The Companies use test barrels which will give us much different velocities. Good luck, DougC Link to comment Share on other sites More sharing options...
PingJockey Posted October 19, 2012 Share Posted October 19, 2012 Ok, I guess I didn't understand your question. The FP has less internal case volume since it is pushed deeper into the case, so it needs less powder for a given velocity vs. the Round nose bullet not as deep in the case. The RN needs more powder due to more internal volume to make the same PF. This will account for the difference in powder charge. Remember that VV data is a guide for the end user. The Companies use test barrels which will give us much different velocities. Good luck, DougC Doug If you look at the two loads in question, you will see that the Lapua RN actually shows less powder than the Hornady FP. That is where the confusion is, at least for me. At any rate, if he uses the FP data for a RN bullet as a starting point, he should be good to go. Link to comment Share on other sites More sharing options...
DRobson Posted October 19, 2012 Share Posted October 19, 2012 I was using 5.0gr N340 with a PD 124FMJ @ 1.145 In a 5" STI I averaged 1100fps In a 5" m&p I averaged 1115fps No pressure signs and a very accurate load. Link to comment Share on other sites More sharing options...
ZombieHunter Posted October 20, 2012 Author Share Posted October 20, 2012 Well, I went and fired off a few of them - didn't notice any pressure signs, but it is definitely a very stout load. Am interested in what the chrono will show next.. I predict 1150-1190 fps. I'll post my results next week when I'm able to get out to the range. Thanks for the replies! Link to comment Share on other sites More sharing options...
PingJockey Posted October 20, 2012 Share Posted October 20, 2012 (edited) Well, I went and fired off a few of them - didn't notice any pressure signs, but it is definitely a very stout load. Am interested in what the chrono will show next.. I predict 1150-1190 fps. I'll post my results next week when I'm able to get out to the range. Thanks for the replies! Was that the 5.6 load? Edited October 20, 2012 by PingJockey Link to comment Share on other sites More sharing options...
ZombieHunter Posted October 20, 2012 Author Share Posted October 20, 2012 (edited) Was that the 5.6 load? Yes Edited October 20, 2012 by ZombieHunter Link to comment Share on other sites More sharing options...
PingJockey Posted October 20, 2012 Share Posted October 20, 2012 I'm gonna try N330 for a "general purpose" load (1150 - 1175 FPS). VV/Lapua claims that N330 was designed specifically for 9mm Luger. If the 340 works out for you, I may try that instead. "N330 Burning rate is a bit slower than with N320 and corresponding to Alliant Unique and Vectan Ba 9. Especially designed for 9 mm Luger but also suitable for .38 Special, .40 S&W, .44 S&W Special and .45 (Long) Colt." If you are interested, here is a link to a VV burn rate chart. VV Burn Rate Chart Link to comment Share on other sites More sharing options...
ZombieHunter Posted October 28, 2012 Author Share Posted October 28, 2012 For anyone interested, here is my chrono data out of an M&P Fullsize 9mm Personally, I was a bit surprised by this data; not at all what I expected. But, I've heard from many sources that M&P barrels are quite a bit slower. I fully expected 1200 fps out of the 5.5 load. Link to comment Share on other sites More sharing options...
PingJockey Posted October 28, 2012 Share Posted October 28, 2012 If their are no pressure signs, I would be tempted to bump that up a tenth or two, since VV shows 5.7 as max. The SD sure looks good! BTW, how was the recoil? Link to comment Share on other sites More sharing options...
ZombieHunter Posted October 28, 2012 Author Share Posted October 28, 2012 I noticed between 5.5 and 5.6 the FPS pretty much stayed the same and some shots went down; so I assumed I was right near the max pressure; but hard to say really. Recoil wasn't bad at all, not what I was expecting (for a 9mm anyway). But it was significant enough to really slow down target reacquisition IMO, from what I'm used to using N320 at around 1060 fps. Link to comment Share on other sites More sharing options...
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