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[ARCHIVED THREAD] - 6.8mm SPC FAQ & Load Data Part III (Page 2 of 20)
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The Krieger stub is only rough chambered so I can cut the chamber to any headspace spec. I usually split the difference between go and no-go. I have not had any ammo-fit issues, so you should be good. If you want, I can chamber on the long end, but you are only talking 0.001" to 0.002" difference. |
Another way to find out what the correct trim length is for YOUR chamber is to get a chamber length gauge (insert) from Sinclair. It's an inexpensive caliber specific plug that you insert into a shortened sized case. You shorten the neck on the test case by .100". (So for 6.8 SPC you trim a case down to 1.576") That's right, you sacrefice a case for this operation. Then you put the chamber length plug into the case and chamber it. The plug is made of leaded steel so as not to hurt the chamber... In the past I've found factory chambers to be Loooong! My Remington M700 6.8SPC doesn't have too much growth space before I need to trim, however. (less freebore correct?) Couple that with soft Remington brass and you have a trimming nightmare. Silver State Brass here I come...  ETA: you have to drill out the primer pocket so you can use a punch to remove the chamber length gauge (plug) when you're finished. |
Ok, good deal. Would you mind emailing me and let me know what I owe you and a rough eta? i know you're real busy right now but would just like to have a rough idea. Thank you again. |
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Thanks watersniper. I have 20 pieces of newRemmington brass to experiment with, so I don't mind 'sacrificing' one of them. (I had planned on using them to make a few dummy rounds anyway). But it looks like I won't be reloading for a while. My Lyman universal trimmer broke after my first piece of brass, now it's got to be sent back to the factory for replacement.  .
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Or you could go with the SSA stuff: Silver State Armory $24/100 or $110/500 Hmmm......maybe I should get myself 500 pieces of the SSA. 
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Go with the Silver State. It is stronger in the casehead area. 
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+1 Also, as the brass is tougher/harder in general, you won't find yourself trimming the cases every time you reload them. Stephen |
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The 6.8 was designed with the small rifle primer but it was Remington who wanted the large primer. When we were asked to make it they kept the large rifle primer so as to compare apples to apples. Recently Military types asked us to switch to the small rifle primers and all our testing indicates that we lose nothing. With some lighter projectile you will even see less veretical spread with the small rifle primers We have made our last run with the large and we are switching to the small rifle primer. Art - SSA |
Art: That is good to hear with SSA and Hornady having small rifle primers maybe Remington will make the switch also. Joe |
With the small powder charges and type of powders suitable (ie. burn rate) for use, standard primers are more than sufficient. |
Which projectile are you having feeding problems with? The Barrett which we have here had no issues with any of our loads. The Barrett has an M4 feed ramp so it should feed well even with the X-Treme which has a blunt tip. We did have to adjust the feed lips of one of our PRI mags to get it to feed properly, it was not feeding 100% of the time no matter what we put thru it. Art - SSA |
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Range report using H4198: Temp 92F Wind 0-5mph Range 100 yds. Model1Sales Upper with Shaw 16" barrel Midwest FF Railed HG Stock USGI trigger (~7lbs) PRS Stock Leupold 2x7 Scope Load 1 22gr H4198 110gr Sierra ProHunter bullets CCI Benchrest Large Rifle Primer Rem Cases Avg. Spread 1.56" Load2 23gr H4198 110gr Sierra ProHunter bullets CCI Benchrest Large Rifle Primer Rem Cases Avg. Spread 1.44" *Best Group 1.18" Load3 22gr H4198 110gr Sierra ProHunter bullets Win 215 Magnum Primer Rem Cases Avg. Spread 1.92" I think with a match trigger 1" or less group are attainable with this setup. No signs of excessive pressure from these loads.  |
A better trigger will definitely improve the groups. Hell, a reduced spring set would do wonders. Are you pulling shots to the right ot left? JP Enterprises for $10 Superior Shooting Sytems (Tubbs) for $16 Wish you had access to a chronograph............. |
Wish I had a chrono too. Maybe I will get one soon. Shots are stringing horizontaly. My best group was lined up side-by-side at almost the exact same level. |
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Today's range trip with the 6.8. Groups go sub-MOA! Again Model 1 Sales upper 16" barrel MI Free float tube 2x7 Leupold Scope I also performed the 15min trigger job on it All 3 loads tested had atleast 1 Sub 1" group! I am pleased with it. 26gr H4198 90gr Sierra HP Avg group 1.09" Best .905" 27gr H4198 90gr Sierra HP Avg group 1.00" Best .692" 24grH4198 110gr Sierra Pro Hunter Spire point Avg Group 1.51" Best .687" |
Damn Bubba, I know I don't have to tell you, but your 6.8 is HOT. I love that magpul stock. Why no magpul (or other aftermarket) grip yet? Yes, this is a little off topic, but how well does your rifle balance with the PRS? Is it "muzzle light" (sounds better than "butt heavy"  )I'm thinking of something like that for my next project in 6.8 (or maybe a DPMS .260) so thanks for the pic. Again, very cool! Scot |
| I have noticed alot of inconsistency in the 6.8 SPC world here lately. It seems that now that there are three sets of trim lengths listed in this thread. This can confuse new folks at the 6.8 game. It seems that many of the ammo makers are doing things differently ie; primer sizes, case thickness, and anything else. The barrel makers don't thread them all with the same thread pitch. This makes things hard for flash hiders and suppressor mounts. I thought that we had industry standards. I think that Remington should have done more R&D on this round before it was released. It would just be nice to have industry standards on this stuff, so everyone would be on the same sheet of music. It would also make the 6.8 SPC more friendly to new users. Don't get me wrong, I like the 6.8 SPC alot and wouldn't trade mine for anything. Just would like to see some of these things cleared up to promote the round. The better manufacturers do things more in line with the correct specs. Just my 2 cents..... |
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silentbushmaster, Agreed 100%! Some of these things ought to be "spec" and some of them are convention. Later entries to the 6.8 market should look at the original and existing guns in the market to figure out how to retain compatibility. The ammo and chamber issue is "spec." There is no excuse for the chamber dimension confusion, and everyone involved in 6.8 needs to help the industry get standardized on the right chamber ASAP (IMO, it's the one that shoots full-power ammunition, like all the original ones do). The thread pattern issue is "convention." There is no excuse for manufacturers using the 9mm thread pattern, besides convenience, when the 5/8-24 is the de-facto standard. |
How did the Barnes Triple Shock work out? Art - SSA |
I just got off the phone with Noveske and they have done their 7.5" Diplomat in 6.8mm SPC before. It is a special order item taking 10-12 weeks. I guess there's nothing left to do but get out the checkbook and start waiting... Stephen |
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Nevermind- for future reference, it's #19 for RCBS shellholder and #15 for Lyman SH. |
Thanks for the compliment on the gun. The PRS stock is fairly heavy, but balances out the rifle length handguard on the 16" barrel. It actually balances very evenly. |
Are there any preferences in bolt carrier weights for 6.8spc? i.e., AR vs M16, added weight to carrier? Any recommended buffer for best operation, or is a stock Colt AR/M16A2 buffer 'just right'? [Let's not get into discussion of whose Brand X custom nonstatndard aftermarket part is best.] Bill Wiese San Jose |
I setup all my barrels with a fully shrouded AR-15 carrier, so it's a little bit heavier than an SP1 carrier, but not as heavy as an M16 carrier and there are certainly no extra weights of heavy buffers needed. Most of the uppers out there are made with Shaw barrels and these seem to be running just fine with standard buffers and carriers. There are really so FEW barrels and uppers, that we don't have 10,000 samples to look at to see a real trend. I don't know what Brand X uses in their uppers, you would have to ask them... www.brandx.com As the cartridge is still pretty new, barrel makers have the ability to develop gas port sizes properly to run best with standard components and this is the ideal situation. |
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I think Randall has it pretty much nailed down, the m16 carrier would be my first choice far any caliber. If you are one of those who prefers not to go with the m16 carrier one like the Rock River full circle shrouded carrier would be the next best thing. I have stuck with the standard weight buffer for both collapsible and rifle stocks, and it works just fine for me. Again if you feel the added weight is a plus by all means go for it. Maybe it is just me but I would rather try to get a AR up and running with standard parts first. Then if there is a problem it will be easier to sort out. Joe |
I use the cardboard/styrofoam .223 boxes for my reloads and my loads are 2.3" OAL. They are a snug fit but not bad. You just push the rounds down a little bit and it works fine. It has moreto do with the diameter than the length. I don't know about the plastic boxes. I guess it would depend on just how big each little square actually is. Length should not be a problem unless you are loading really long. |
[ARCHIVED THREAD] - 6.8mm SPC FAQ & Load Data Part III (Page 2 of 20)
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