[snaz567]

I had bought a box of these when I was first starting reloading to use for subsonic rounds. They are bit too long for the CProducts magazines I have to function properly. What I was thinking of doing was loading some of these up tonight w/RL10x and H322. I was planning on just barely seating them into the brass and then dropping the bolt home. Taking a measurement and then maybe dropping them back a few thousands on an inch off of the lands. Much like the guys shooting the 80 and 90 grain 223 rounds are doing for competition. I really have no other use for these and as they won't reach magazine length anyway, I don't really lose anything loading up single shot style.

Has anyone else tried this and does anyone have any suggestions? Any ideas on much higher I can load since the pressure levels should drop?

I was mainly just curious as too how much velocity I can get by increasing the COAL, more case capacity/less pressure as a result while using these higher BC bullets. I thought I might be able to load up a decent LR round. According to JBM's caculations, if I could get them up 2500fps, they would still be traveling 1135fps @ 1K yrd w/44.0 MOA of drop.

In comparision, my 308 (yes, It'll still feed from the magazine however) w/168gr smk's handloads are 2524fps at the muzzle and is still traveling 1105fps @ 1k, w/44.9 MOA of drop.

The published B.C. of the 0.277 135 SMK is 0.488 and the .308 168gr SMK B.C. is 0.462.

Any thoughts or suggestions would be appreciated. If anyone else has tried this (I'm sure someone else has) your input would be appreciated as well.

Thanks in advance.

 

[Jamesb74]

You can do it I would suggest coloring the bullet with a sharpie and doing it several times for an average comparision. Slamming the bolt home can have an effect on just how long or short the throat is. I mean by showing you how far off the lands are. They will definitly be one shots as they won't work in the mags. I would say start with data you already have and work up slowly watching for signs.

 

[snaz567]

That's what I did. I reach the lands @ COAL of 2.544". So I was thinking of bumping that back to 2.540" or 2.535". Any suggestions on that? I have to do some reading. I've only ever reloading for Semi's, so I can't remember what I've read about reloading for bolts and single shots. I can't remember if most people start 0.005" or 0.050" off of the lands.

 

[Jamesb74]

You can sart at either. There are a few that start them on the lands. I did most of my handloading for bolts before finding the ar. So I am kind of opposite. If your going to hand feed them in then start .050 back and move forward if you want.

 

[snaz567]

Will do. Thanks for the help.

 

[constructor]

Talk to HTR also he is working on some subloads with the 135.

 

[snaz567]

Didn't work so great for me. The fastest I got before swipes was about 2350fps. My best group was right at 1.5" @ 125yrds.

 

[TackDriver68]

I tried loading these also. mag lenth and single shot.

best group was 2"+ at 100yds.

tried loading with:
RE7
H322
H335
Benchmark

my guess is they would be nice in a bolt gun with a long barrel...20"-26"

and maybe vargret or BL-C2?

That being said I have had excellent results with the Nosler 130gr BT Hunting (accubond is too long) and,
130gr Nosler SP(discontinued) and the 130 Gameking(the one with the boattail) and Benchmark powder.

 

[snaz567]

Thanks for then info. I've had good luck w/the 130 BT's so far. I only started loading them up full power and some for sub sonic when there was no other bullets to be found. I still have a lot of work to do w/them. I've only tried BLC-2 and H322 so far. I haven't found the max yet w/the BLC-2 and I still need to try 10x and H335 w/them. I was getting sub .75MOA w/both of the powders I tried tho.

 

[Test_User]

Also jsut so someone says it as long as you account for it there is nothing wrong with having your bullets on single loads touching or even seated into the lands. Most BR and LR shooter do this as the SOP. As these are going to be sub load anyway so peak pressure is never going to be an issue why not seat them so thay are actually touching the lands. Infact soft seating them and allowing them to seat themsleves off the lands woudl work as well. For sub load recipients HTR and C and your best bet.

 

[Jamesb74]

Also jsut so someone says it as long as you account for it there is nothing wrong with having your bullets on single loads touching or even seated into the lands. Most BR and LR shooter do this as the SOP. As these are going to be sub load anyway so peak pressure is never going to be an issue why not seat them so thay are actually touching the lands. Infact soft seating them and allowing them to seat themsleves off the lands woudl work as well. For sub load recipients HTR and C and your best bet.

I was wondering about that. And yes it pretty much is SOP for bolts. I do it myself all the time. But I am not the familiar with seating them in semi auto's and was wondering if the force of the bolt closing could inadvertently force the bullet to soft seat to much. it is a lot more forceful than closing a bolt action or a single shot action so I didn't want to advise incorrectly.

Hadn't had a chance yet to play with it this way but I was getting to it.

 

[borderpatrol]

I had bought a box of these when I was first starting reloading to use for subsonic rounds. They are bit too long for the CProducts magazines I have to function properly. What I was thinking of doing was loading some of these up tonight w/RL10x and H322. I was planning on just barely seating them into the brass and then dropping the bolt home. Taking a measurement and then maybe dropping them back a few thousands on an inch off of the lands. Much like the guys shooting the 80 and 90 grain 223 rounds are doing for competition. I really have no other use for these and as they won't reach magazine length anyway, I don't really lose anything loading up single shot style.

Has anyone else tried this and does anyone have any suggestions? Any ideas on much higher I can load since the pressure levels should drop?

I was mainly just curious as too how much velocity I can get by increasing the COAL, more case capacity/less pressure as a result while using these higher BC bullets. I thought I might be able to load up a decent LR round. According to JBM's caculations, if I could get them up 2500fps, they would still be traveling 1135fps @ 1K yrd w/44.0 MOA of drop.

In comparision, my 308 (yes, It'll still feed from the magazine however) w/168gr smk's handloads are 2524fps at the muzzle and is still traveling 1105fps @ 1k, w/44.9 MOA of drop.

The published B.C. of the 0.277 135 SMK is 0.488 and the .308 168gr SMK B.C. is 0.462.

Any thoughts or suggestions would be appreciated. If anyone else has tried this (I'm sure someone else has) your input would be appreciated as well.

Thanks in advance.

Sierra's posted data is velocity specific. You have to look down their scale to find the B.C.'s for 6.8SPC velocities. In your other post you found your OAL the old fashioned way, I'd subtract .015" for a slight jump and see how it works. .025" jump sometimes works well too. I've always been interested in the 135 SMK in this caliber because it actually has a boatail, unlike their 115's.

 

[snaz567]

Sierra's posted data is velocity specific. You have to look down their scale to find the B.C.'s for 6.8SPC velocities. In your other post you found your OAL the old fashioned way, I'd subtract .015" for a slight jump and see how it works. .025" jump sometimes works well too. I've always been interested in the 135 SMK in this caliber because it actually has a boatail, unlike their 115's.

I've downloaded sierra's B.C. chart for figuring this, but didn't take the time to look at it when I OP'd. So I just used the published B.C. I just couldn't get great accuracy or enough fps to make it worthwile IMHO. If you have better luck, please post your results. My COAL was 0.050 off of the lands at 2.500". Maybe placing it closer as you and Tim W suggested would be a better result.