I've only loaded XLC's (165's and 180's) in a 308 Win... though fouling was reduced, there was zero change in velocity even though I upped the powder charges. I called Barnes and they were a bit puzzled as they claim a 100-200 fps increase in velocity with the XLC's over standard X's. The tech-rep at Barnes thought that perhaps there wasn't enough powder capacity in the 308 hull to take advantage of the XLC's. He really had no answers.
Personably I think Barnes is full of crap. No bullet lubricant is going to give you an increase of 100-200 ft/sec. As is well documented, lubricated bullets generally lower pressure a little and is accompanied by a slight REDUCTION in muzzle velocity. The idea that you can now increase the powder charge, while still working in the same pressure area, and achieve significant increases in velocity is just not believable. Barnes has been telling that story for a long time but I doubt that you will find too many handloaders that will tell you that they have experienced this. Anyone who is getting noticeably higher velocities is likely to have much higher chamber pressure but just might not know it. Solve all your problems and rechamber your rifle to 300WSM. Light loads with low pressure will still produce more velocity with the same .308 bullet.
It depends upon to what they're comparing them. I could definately see a gain in the 100 fps range--compared to the uncoated, flatbase X bullets since those are usually anywhere from 50-100 fps slower than "regular" bullets.
So, if the coating reduces their friction to the point that it's equal or even a little less than a "regular" bullet, a 100 fps gain (over the uncoated FB X's) seems plausible to me.
Hopefully I'll get a chance to do some strain-guage work this summer and actually measure the difference in pressure the coating makes.
Posts: 920 | Location: Mukilteo, WA | Registered: 29 November 2001
I gotta admit I'm with Varmithunter on this one. I think you could get a slight bump in velocity but I think their claims of 100-200 fps are terrrrrrrrificly optimistic! I'm thinking the best case scenario is 50-75 fps and any other gains from that are just plain jumps in pressure. I know some of the guys on this forum are starting to spend money on pressure testing equipment. Maybe some of them are barnes lovers and can experiment for us a little. Just so you know I'm not prejudiced I do shoot reg barnes, barnes xlc, and barnes I've molycoated myself. FYI According to quickload 3230 is achievable at 62,000psi in a 24" barrel in a 7 mag so, I'm not sure I'd give credit to the blue coating.
quote:Originally posted by Brad: I've only loaded XLC's (165's and 180's) in a 308 Win... though fouling was reduced, there was zero change in velocity even though I upped the powder charges. I called Barnes and they were a bit puzzled as they claim a 100-200 fps increase in velocity with the XLC's over standard X's. The tech-rep at Barnes thought that perhaps there wasn't enough powder capacity in the 308 hull to take advantage of the XLC's. He really had no answers.
What has your experience been with XLC's?
Have you experienced velocity increases?
Brad
In my experience,it's true. Period.
Go with a faster powder, at equal charges of a slower one. Example, a .300 Win Mag from 3050 fps to 3220 fps. Ruger KM77RSP 24" barrel. Old load, 78.5 R22, new load of 78.5 R19 and the Barnes XLC.
I've hunted a lot, also in Africa, and performance...is one-shot kills, boring to say the least.
IMHO, Gustavo
Posts: 753 | Location: Buenos Aires, Argentina | Registered: 14 January 2001
Gustovo-Was that a 165 bullet? According to quickload if it was a 165 your velocity is achievable with a max load and an uncoated bullet. I don't think it was the blue coating that got you there as much as the switch to the faster burning powder in a 24" barrel. The bottom line probably isn't worth worrying about. Evidently you have a great, fast moving, highly ballistic coefficient, bullet working for you. (And I'm assuming you're getting good accuracy too). Your combo treads on the heels of any 300 wby with a 180 grain bullet!!
Does anyone know why the Barnes website shows the Ballistic Coefficient for the 180gr XBT at 0.552 but they show the XLC BT bullet at 0.511? Isn't the only difference in bullets the fact that the XLC is coated?
Posts: 117 | Location: Tumwater, Washington | Registered: 13 January 2002
quote:Originally posted by Don Krakenberger: Gustovo-Was that a 165 bullet? According to quickload if it was a 165 your velocity is achievable with a max load and an uncoated bullet. I don't think it was the blue coating that got you there as much as the switch to the faster burning powder in a 24" barrel. The bottom line probably isn't worth worrying about. Evidently you have a great, fast moving, highly ballistic coefficient, bullet working for you. (And I'm assuming you're getting good accuracy too). Your combo treads on the heels of any 300 wby with a 180 grain bullet!!
Don, sorry for my mistake...I just forgot to say that the bullet weight was 180 grains!!
I use QuickLoad, and as you may know is a fairly good predictor but not perfect.
I know, my pressure readings...maybe a bit high but safe. I hunted with these loads a lot, and in very hot weather, and never had a problem. Accuracy is about 1.5" at 164yds (150 meters)
Regards, Gustavo
In the "Your Favorite Loads - Share Them With Us" section is the complete data for the load.
Posts: 753 | Location: Buenos Aires, Argentina | Registered: 14 January 2001
Gustavo--WOW--that's pretty awsome out of a 24" barrel. I don't know why but the ruger's I've chronied have never been on the fast side. I have a 300 wby that I think is "fast". I can push a nosler 180 or a 180 xbt at about 3325 fps (That's out of a 26" barrel) and I figure that with the extractor marks and primer pocket life I'm pushing about 65-70,000 psi.
Don, in order to be sure of the chrono readings, a couple of weeks ago I mounted two chronos (a Chrony Beta Master on a PACT PC2) and this way I got simultaneous readings.
The differences were minimal! the highest was 3 FPS !!
So I concluded that the velocity was in fact there...
Regards, Gustavo
Posts: 753 | Location: Buenos Aires, Argentina | Registered: 14 January 2001
I shoot the 140 Barnes XBTLC in my 7mm Rem Mag. It does have a 27.5" barrel. I use 71 grains of RL22 and get 3330 fps. 72 grains seemed safe and gave about 3400 fps but 71 grains was more accurate. I do not know what I could do with the uncoated bullet. Rufous.
Posts: 224 | Location: Walla Walla, WA 99362 | Registered: 05 December 2001
Gustavo, Not argueing but when you say go with a faster powder with equal charges of a slower one are'nt you in turn increasing pressure thus the increase in velocity.
quote:Originally posted by heavy varmint: Gustavo, Not argueing but when you say go with a faster powder with equal charges of a slower one are'nt you in turn increasing pressure thus the increase in velocity.
Absolutely true!!
Posts: 753 | Location: Buenos Aires, Argentina | Registered: 14 January 2001
