6.8mm SPC FAQ & Load Data - Page 2

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[ARCHIVED THREAD] - 6.8mm SPC FAQ & Load Data (Page 2 of 20)

Posted: 7/14/2004 8:00:02 AM EDT

[#1]

I am trying to find a high quality 6.8 barrel, 16", midlength, mill-black not silver, preferabaly with a dovetail gas block. Due to finances, I am better off buying a 6.8 rifle peice by peice. Any help would be appreciated.
Edited to add-
Also who sells lower receivers marked in 6.8? I am a bit of a perfectionist and do not want 5.56 marked onto a 6.8 weapon. Either that or lower receivers with no caliber markings?

So far troy is the only one I have found, selling the complete upper.

Posted: 7/14/2004 9:14:30 AM EDT

[#2]

I think it's easier and cheaper to just get a kit from some place like Model 1 Sales. If you do the math for just a bit more then you'd pay for an upper you can get a full parts kit so you'll have extra parts if you've already got a complete lower and they won't cost near as much as if you'd have bought them seperate.

Posted: 7/14/2004 2:56:18 PM EDT

[#3]

I was debating on wether to tell ya'll about this or not, guess I can trust you not to buy out the guys supply.
Widener's Reloading & Shooting Supply, Inc in Hohnson City , TN(1-800-615-3006) is listing 6.8Rem. brass for $21/100 or $103/500. I've not called to see if it's in stock, I assume it is or they'd not list it. That's not a bad price, now if we could just get some loading date we'd be in hog heaven. Just make sure you save some for me.LOL

Posted: 7/14/2004 5:51:22 PM EDT

[#4]

TNFrank,

Thanks for the tip on brass. Midway was listing it for a while, but they never had any in stock.

If you need loading data, send me an email and I can help you out once you are ready to go.

-z

Posted: 7/15/2004 1:05:13 PM EDT

[#5]

Called Wideners' they dont have any but hope to have some around the beginning of August
or mid-August. Fred Huntington and several other outfits have the brass, and factory ammo
cataloged, but thus far no one has any.

However, having said the above, P.R.i (Dave Dunlap) has indicated that they are willing to
sell some 6.8x43 empties (once fired brass from their testing the weapons) for $32/100
plus shipping. *please note that they (P.R.i) are not in the brass/ammo business, but are
willing to assist shooters in any way they possibly can as the 6.8x43 is quite scarce in
most every aspect.

Or if you are making your own cases from the parent round (.30 REM) Graf & Sons has brass.

And just as an aside, some minor stats between the 6.8mm Remington brass and the .30 REM
that I have formed into the 6.8 are as follows:

10 cases of each: 6.8x43 weigh an average of 125.1 grains +/- .1 grain per case
.30 REM (case formed into 6.8) average 119.7 grains +/- .1 grain per case

So the factory cases ore heavier, but I also checked the case volume of the above and found
both have the same volume, 35 grains (used H335 which is a very small grained ball powder
but perhaps not as dense as had I used water).

The only way to determine where the brass is heavier is to section one, and I can't really
afford to waste 1 piece of brass to do so.

Just an aside

Art

Posted: 7/15/2004 1:56:51 PM EDT

[#6]

I was afraid of that. Guess we'll have to wait a bit for brass/ammo. At least this should turn out to be a "Wal-Mart" caliber once production get's started. That's the one thing the 6.8 will have over the .300 FB and the main reason I'm going with is instead of the .300.

Posted: 7/16/2004 7:38:36 AM EDT

[#7]

I emailed RCBS about the availability of dies and shell holders for the 6.8mm, and they replied they were waiting on "drawings" of the cartridge. They advised me to inquire again in a month. In the meantime, I believe Hornady is already manufacturing dies in this caliber.

Posted: 7/16/2004 8:26:51 AM EDT

[#8]

Quoted:
I emailed RCBS about the availability of dies and shell holders for the 6.8mm, and they replied they were waiting on "drawings" of the cartridge. They advised me to inquire again in a month. In the meantime, I believe Hornady is already manufacturing dies in this caliber.

Midway U.S.A. has Redding dies for $44 bucks. Shell holder is the same as for the .30Remington. Check out the Midway U.S.A. web site for more details. Personally, I"d like to see Lee bring out a set of dies, they'd be less expensive and you'd get a shell holder with em'.

Posted: 7/17/2004 5:46:50 AM EDT

[#9]

Hornady is the only outfit who is currently in production for dies in 6.8mm Remington SPC, and
has them (or did have 10 sets on 22 June 2004) the product number is 544299, the cost
from them is $31.58 plus shipping. When I got mine they indicated distributors had also
received some die sets and the cost, more than likely, would be less then MSRP.

I had also hoped that Lee would have jumped into the fray and begun producing dies, but when
I ordered a custom crimp die and custom length gauge pilot for the cartridge on the 24th, no
one I spoke with there had even heard of the 6.8x43 (6.8mm remington SPC).

However, they now have 3 pieces of fireformed brass to get some measurements from, so who
knows maybe soon they will have some die sets available.

I find it somewhat odd that they do have 4 die sets for the 6.5mm Grendel.

Art

Posted: 7/20/2004 12:24:32 PM EDT

[#10]

who has put the 6.8 on a chrony? I am wondering if it will make 2800 fps with a 115gr bullet. i shoot uspsa and want to go to the 6.8 if it will make the proper power factor.

also who has shot the 6.8 with a ta11 acog, i was wondering about the trajectory difference. it should only matter out to about 300 yrds as that is about the longest range at any match i have been to.

i have a 9mm upper in the equipment exchange i would trade to some 6.8 parts, any takers?

Posted: 7/20/2004 12:27:54 PM EDT

[#11]

tewlman223,

Check out the FAQ tacked in the AR15 forum. I haven't chrono'd any production Remington ammo, 'cause I haven't seen any. The preproduction had known problems and was about 100fps slower.

The BC and MV of 6.8SPC is virtually identical to 75-77gr 5.56mm or 150gr 308, so it will track the reticle as well as those do. In other words, the TA11 is about 5" off at 400yards.

-z

Posted: 7/20/2004 1:05:21 PM EDT

[#12]

well, i might as well jump in and see for myself. if i build an upper and it won't make my power factor, i'm sure somebody here would be interested...

i found the barrel on model 1's sight, but couldn't find the bolt. should i just call them to inquire? i already have an a3 upper, and make my own foregrips.

are the ak style comps really that effective? i was planning on making a titanium comp in the style of the JP bennie coolie comp. that only leaves needing mags.

am i leaving anything out, besides ammo?

Posted: 7/20/2004 1:15:09 PM EDT

[#13]

Mags will be available shortly.

Use the new MSTN/PRI "Q.C." comp in 6.8. I reviewed the 5.56mm version a couple weeks ago (posted here) and it compared favorably to the state of the art 3Gun comps (JP BC, Benny Hill, Miculek).

-z

Posted: 7/20/2004 1:26:50 PM EDT

[#14]

Zak,

all i saw listed on the model 1 sight was 16 and 20 inch barrels, but you mentioned a 18 on your faq. both the model 1 barrels are heavy contour, where can i get an 18 or 20 with a smaller contour? in my game the added weight can really slow you down.

Posted: 7/20/2004 1:41:30 PM EDT

[#15]

MSTN

Posted: 7/20/2004 3:26:43 PM EDT

[#16]

MAGS!

[ link to larger image ]

[ link to larger image ]

What's that muzzle attachment?

Posted: 7/20/2004 4:36:23 PM EDT

[#17]

What brand of magazines are those? Those don't look like the PRI magazines I got. Those also look like 20rd Mags?!?! These are for the 6.8 right??

Posted: 7/20/2004 4:53:24 PM EDT

[#18]

PRI is my guess, by way of MSTN. The kits consist of a magazine body and a follower. You apply such a kit to a preban 5.56mm magazine to convert it to be 6.8-compatible.

Look carefully, there are two lengths, a long and a short. These correspond to the 25 and 15 round capacities.

-z

Posted: 7/21/2004 7:40:24 PM EDT

[#19]

Got an email back from Bushmaster, finally. They said the have all the tooling necessarry to start making 6.8 barrels, but are going to wait till there is widspread availability of the ammo before they start making them. Me personally I think with all the interest in this round that if they made their barrels and started selling them at their regular prices they would make a lot of money right away as I havent found any barrels comparable in price to 5.56. Any predictions when ammo will be readily available?

Posted: 7/22/2004 6:00:52 AM EDT

[#20]

Zak,
what kind of primers are you running? Thanks.

Posted: 7/22/2004 7:12:01 AM EDT

[#21]

If you work up a load the normal way, you should be able to use virtually any large rifle primer. I'm using Federal 210M "Match" primers, because I use them in 308.

-z

Posted: 7/23/2004 5:01:52 AM EDT

[#22]

MrKasab, You might try E.R. Shaw in Pa. They are making the barrels that Model 1 has for the
6.8x43. They can probably help you out.

Art

Posted: 7/23/2004 12:41:59 PM EDT

[#23]

s_s74
Thanks for the tip. Just got an email back from them saying they dont make barrels for semi autos. Guess they wont do it at the individual level.

Anyone know when Remington will have their 6.8 widley accessible, as in a couple hundred rounds in every gunshop? Or any ammo maker for that fact.

Posted: 7/23/2004 8:12:22 PM EDT

[#24]

HAs anyone tried AA 1680 for loading 6.8? It was designed for 7.62x39 and other small capacity cases.
I just finished my first barrel, complicated by my selection of blanks. Lothar Walther's stainless steel is not a good choice for a 12x36" manual lathe. It's much better suited for a high speed CNC production machine.
At any rate, my first upper is finally up and running, with Remington pre production ammo, Continental bolt, and PRI mag, but is not suitable for sale.
At this rate, everyone will have forgotten what 6.8 is, by the time I get finished practicing barrel making...

Posted: 7/23/2004 8:16:40 PM EDT

[#25]

I haven't tried it yet. I just loaded up some experiments using N133 and RL10x. Will shoot those tomorrow if it stops raining ever. Next on the list in Benchmark, but it was out of stock.

The three I've already tried are AA2230, N135, and N140.

I'm using the 110gr VMAX as standard, but I'm also trying the 90gr Speer Varminter.

I do have a bunch of pulled 115gr bullets.

-z

Posted: 7/23/2004 8:38:21 PM EDT

[#26]

I played with VV N135 and N140 while working on 500gr 499 LWR loads, and couldn't get enough powder in the case to get them much past subsonic. The AA 1680 was able to push them to around 1400 fpm. It might be worth a try.

Posted: 7/23/2004 8:43:37 PM EDT

[#27]

Thanks for the tip. I'll see if I can get some this weekend.

About 28.5gr of N135 will fit in the 6.8SPC case, to the bottom of the neck. This is only good for about 2500fps with the 110gr VMAX, a little more with the 115gr OTM. N140 being slower is even worse.

-z

Posted: 7/25/2004 2:46:33 PM EDT

[#28]

1680 didn't work out so well. I think it's too fast for this cartridge.

Here's the summary from today. OAL is max to fit in a colt 20 round, temp 85F, elevation 5000'. 110gr VMAX was used.

Controls:
My old standard load of N135 was shooting at 2523 - 2535fps (sd 5 - 11fps)
Same load but using pulled 115gr OTM bullets was 2503fps (sd 35fps)
Preproduction Factory 115gr: 2742fps (sd 36fps)

New experiments:
RL10x, 110gr VMAX, primed cases pulled from preprod ammo: 2668fps (14.3)
VV-N133, everything else the same. 110gr VMAX: 2591fps (20.5)
AA 1680, everything else the same. 110gr VMAX: didn't run well at 2644fps, seeping gas through primer pocket at just over 2700fps.

Compared to my base load of N135, N133 is a little better, and RL10x is a little better still. It's still about 120fps slower than I'd like to be. AA1680 has great density, but it seems to be too fast. Something as dense as 1680 but slower would work better.

A friend has suggested Benchmark (not sure if it's BM1 or BM2), and I haven't tried H322 or RL7 yet.

Once again, don't try to replicate this data unless you know what you're doing.

-z

Posted: 7/25/2004 4:48:06 PM EDT

[#29]

Zak, do you have any idea where your OAL is in relation to the rifling? Are you touching?

Posted: 7/25/2004 6:30:09 PM EDT

[#30]

I'm seating at the max OAL which will fit in a magazine. I don't think it's touching, but I haven't checked.

Since everything is the same length and the same bullet, I don't think I'd see anything different with 1680 alone.

-z

Posted: 7/25/2004 6:43:35 PM EDT

[#31]

Just for sh%ts and giggles, try loading a few more with the 1680, but load them .050" shorter.

Posted: 7/28/2004 2:54:42 PM EDT

[#32]

For those of you who reload the 6.8 SPC what case length is correct, I only have one loaded round to measure and it is 1.675 inch is this correct. Just received my set of Redding dies from Midway USA and reformed some .25 Remington brass I had on hand. The cases looked good but it leaves a lot to trim off. Anyone try the Hodgdon powders yet because this is what I have on hand.

Joe

Posted: 7/28/2004 9:44:43 PM EDT

[#33]

The results with Benchmark were poor. At max case capacity, it was still under 2600fps.

-z

Posted: 7/29/2004 5:41:56 PM EDT

[#34]

J-A-R, the one I just measured was 2.677.

-z

Posted: 8/1/2004 5:36:40 PM EDT

[#35]

HAS ANYONE TRIED THE MODEL 1 SALES KITS YET?

Posted: 8/2/2004 5:21:07 AM EDT

[#36]

I have the Model 1 C.A.R and it performs wonderfully. No problems yet with it. It is mated with a Stags Arms lower receiver.

Edited to show Range Report:
Fine tuned the open sights on my 16" C.A.R today on the range. At 50 yards I was grouping 3 shots in 1 1/2 inch groups. Went to 100 yards and was grouping 3 shots in 4 1/2 inch groups. This was with the Remington 115grain OTM pre-production ammo.
Weather conditions were partly cloudy, mid 80's, with about a 5-10mph breeze.

I hope to tighten these groups up and extend the range and let you all know how it goes. But very impressed so far.

Posted: 8/2/2004 5:10:11 PM EDT

[#37]

this is the 6.8 kit? (just to clarify)

Posted: 8/2/2004 5:18:37 PM EDT

[#38]

Yes, It was the Model 1 Sales 16" C.A.R. 6.8mm Rem SPC kit. All I did was purchase a Stag Arms lower receiver and a few PRI 6.8 10round magazines and assembled.

Posted: 8/2/2004 5:19:24 PM EDT

[#39]

Navy4life,

That preproduction ammo sucks. The stuff I have shoots like 3-4" groups at 50 yards.

Handloads are shooting into touching holes at 50 yards.

Best bets for powder right now look like RL10X and H335. I will have more data within a week.

-z

Posted: 8/2/2004 5:24:03 PM EDT

[#40]

I did notice that every few rounds there seemed to be an odd ball that shot out of group. I just attributted it to me not paying attention to detail and/or a factory defect. Once my press and accessories get here and I build my knowledge base up by reading acouple of those reloading books I plan on reloading and hopefully like you said that will help tighten my groups up too.

Posted: 8/2/2004 5:25:43 PM EDT

[#41]

I always shoot 5-shot groups. It's too easy to get a fluke great 3 shot group which is not representative of the rifle & ammo.

Posted: 8/2/2004 5:32:52 PM EDT

[#42]

I will give the 5 shot atry next time I am at the range. I got a two groups that two of the three rounds were touching sides but I wrote those off as pure luck because I know that my shooting is not to that level yet. With my scoped .280 I can touch rounds in groups all day at 100 yards. But open sight is another thing for me. My first hour at the range my shots were pretty wide groups but after I started getting a feel for my sights and adjusting I started to get tighter groups. And once I finally had a guy at the range lend me some sandbags to shoot off of.

Posted: 8/3/2004 12:08:15 PM EDT

[#43]

Zak:
would like to know how many grains of H335 is a good starting point, when I run this on my reloading software it shows 26.2 grains with the Hornady 110 grain V-MAX bullet. I am using a case capacity of 35 grains of water to base the overall volume and case dimensions from one loaded Remington cartridge. This is new territory here and your input is greatly appreciated.

Thanks
Joe

Posted: 8/3/2004 12:20:26 PM EDT

[#44]

Joe,

Email me at [email protected] and I'll hook you up with a good starting point and a computed "MAX" for H335. The 26gr starting point for H335 should be safe and was very sedate in my gun. I have no idea what or how consistent the chamber and leade dimensions are in the Model 1 and Barrett barrels, however. Just make sure the ogive isn't jamming into the lands. I am using 2.285" OAL. The PRI mags are big enough to run loads over 2.300".

The difference between RL10X and H335 is that RL10x will reach max pressure with less case capacity taken up.

I'm planning to post some suggested loads here for public consumption, but only after I do some more analysis. I need to simulate the internal ballistics and then cross-check with the chronograph.

I'm trying to get that out ASAP, but things are busy. I've got matches and practice the next two weekends, and then RM3G and the ITRC the two following weeks.

-z

Posted: 8/3/2004 3:03:22 PM EDT

[#45]

NAVY- thanks a ton- given me new hope for the 6.8.

ZAK- thanks to you, too, sounds liek you are being the needed guinea pig for the handloads- cheers for your efforts!

Posted: 8/3/2004 4:06:43 PM EDT

[#46]

Zak is that man! One of the true pioneers in the reloading and testing on the 6.8mm Remington SPC.

My hats off to you and all that are paving the way to knowledge on and about the 6.8mm Rem SPC!

Posted: 8/3/2004 11:46:30 PM EDT

[#47]

Quoted:
For those of you who reload the 6.8 SPC what case length is correct, I only have one loaded round to measure and it is 1.675 inch is this correct. Just received my set of Redding dies from Midway USA and reformed some .25 Remington brass I had on hand. The cases looked good but it leaves a lot to trim off. Anyone try the Hodgdon powders yet because this is what I have on hand.

Joe

Found this searching for info on the 6.8mm spc.

ammoguide.com/cgi-bin/ai.cgi?sn=VUxLQKXLBn&catid=263

I am in the process of putting together a 6.8 myself. Ordered a barrel & bolt and a few other parts from Model 1. Have aa RRA laser marked upper coming from RB Precision. Dies coming from Midway USA. Have an RRA lower all but put together. However, I still need useable mags and ammo or brass. I guess by what has been said MSTN would be the best bet with their conversion kits for mags. Guess I'll have to wait for ammo/brass. Would get into the fray, but not quite ready yet so I hope somebody comes up with something or my remaining needs are met.

While searching for info I came across something on the SSK site about the 6.8 being a close ballistic comparison to the .270 JDJ. But I believe that the JDJ is based on the .444 Marlin which would not make for good load correlation ideas.

Good luck gentlemen. Hope to jump in with both feet soon.

Posted: 8/5/2004 6:15:56 AM EDT

[#48]

An easier link to the ammoguide page for the 6.8 is
6.8mm Remington SPC - ammoguide.com/?catid=263

(There's an "Easy Link" on each page that will get you into each cartridge without logging in.)

BTW, ammoguide is looking for UNCOPYRIGHTED 6.8mm load data and will give away a free year's subscription to a 6.8mm owner who can provide same. Contact [email protected] for details.

Mike