First Experiences with the 6SLR

[kyreloader]

I bought a Broughton barrel for my Savage target action on this sight chambered in 6SLR. I then sent it to Kevin Rayhill for a recrown. I wanted to shoot the 105 Berger Hybrids. Reading about the caliber, I then bought 100 Winchester .243 cases and the Redding Type S bushing die from Robert (http://www.6mmar.com/Super_LR.html). I sprayed some cases with OneShot and formed the cases without any problems.

I then took the cases, put Fed210M primers, 43.5g of H4831SC powder and the 105g Hybrids. I loaded 10-5 thous into the lands, 10 at the lands, 10-5 thous off the lands, 10-10 thous off, and finally 10-15 thous off the lands. The 10 that were loaded 5 thous into the lands were used for foulers and getting my 300 yard zero(different scope on action).

I then shot 2 five shot groups with each setting at 300 yards. To my surprise, they shot extremely well. The average moa (per On-Target) groups for each seating depth were as follows:

At lands: 0.561 MOA
5 thous off: 0.374 MOA
10 thous: 0.480 MOA
15 thous 0.546 MOA

So with off the shelf brass with no prep, a load listed on a website, brass formed only with a die(no fireforming)-I was able to shoot 8 five shot groups with an average spread of 0.490 MOA.

Our goal for our F-class rifles are 1 inch 5 shot groups at 300 yards. With some brass prep and fireformed brass- I may have a combination that can do that.

So far so good. I am pumped.

 

[xdeano]

Did you get any velocity readings on any of those groups?

The really cool thing are the numbers come out pretty small. ES/SD's coming in single digits, which means consistency. And all out of a cheap winchester brass without any prep. Who needs to buy $100 brass and all the prep work for worse numbers. It's a no brainer.

Good stuff there Kyreloader! Keep it coming.

xdeano

 

[kyreloader]

I did not have my chrony with me for this range trip. I originally was just playing to fireform the brass. I guess I should have expected more now.

I plan to chrony the next time out, just not sure how quickly that will be.

Any ideas what velocity I can expect? (26" barrel).

(Tinkerer in me still may have to try H1000)

 

[dbforce]

This is nice to know. I have one in the works right now.

 

[xdeano]

My velocity with the H4831sc at 43.5g with Fed210M out of a 24" bartlein barrel was averaging right around the 2824fps. But I'm also at 800ft above sea level, 4 degrees F. it felt like -10F when I was shooting. I've only had it a month and now is not the best time for me to be doing load testing.

With the H1000 I was getting 3027fps out of 48.0g with the Fed210M. but that was at 31 degrees F.

hope that helps. I think with the extra barrel length, you should get a bit more out of it.

xdeano

 

[Bob3700]

I am a bit different in the bullet and bbl dept.

30" - 7.5T Bartline

43.5 Gr H4831sc with 115 DTAC = 3050 fps

.020" into the lands. Winchester brass with Russian primers

Bob

 

[LAKESNAKE]

kyreloader,
Keep us updated.
I will soon be sending my rifle components to Warner Tool Company for a 6mm SLR build.
Stiller Tac 30 W/A action
McMillan A3-5 stock
Bartlein, 1:7.5"5R
I need to go on an order the reamer.
You guys got me pumped.

 

[xdeano]

Bob3700,
That barrel length really adds a lot of velocity to these little bullets. I chopped mine to 24" because I'm also running a can on mine.

xdeano

 

[Julien]

In November I was at the range working uop a load with H1000 and I couldn't for the life of me get the speed up.
I am shooting a 28" Gaillard1-8 twist barrel built on a savage , the temperature was near freezing and I had a full load of h1000 behind berger 105's.

I tried everything to get the speed up more neck tension seated the bullets long ,fed,cci,win primers and the velocity was different with the primers.
So I got in the truck drove home got some different primers in LR magnum ,the speed climbed right up past 3200fps.

Winter is set in now and I will probably only start shooting again in the spring but for sure I am going to try the magnum primers again.
The groups seemed to be the same as regular primers with more speed ,although some people claim grouping is better with regular primers.

I also noticed that day when I cleaned the barrel the first time before using the magnum primers that there was a lot of powder residue
compared to after the mag primers.

 

[spclark]

In November I was at the range working uop a load with H1000 and I couldn't for the life of me get the speed up.
I am shooting a 28" Gaillard1-8 twist barrel built on a savage , the temperature was near freezing and I had a full load of h1000 behind berger 105's.

Is H1000 a popular propellant for that cartridge? My only experience with it was in 300WM & that was years ago. Still I'd be of the opinion that it's on the slow side of what would work best. I shoot a 6XC & have used N540 & N550, H4831SC, RL-17, H4350 and the newer IMR 8208XBR, the last with exceptionally good results on target (@ ~ 3,125 fps) with Berger's 105VLD but admittedly NOT in freezing conditions.

Yes, magnum primers might help with more complete ignition under those conditions but I have to wonder if a slightly faster propellant might also be indicated?

 

[xdeano]

spclark,
It's not the most popular powder for this cartridge, H4831sc is though. I like the H1000 because it's cooler and hence gives me a longer barrel life. here's how mine does at 100yds during a load test. Very low ES/SD's. I'm not doing any weight sorting or bearing surface sorting. Just load and go.

This is 3 shots, i know some like the 5, but i find it a waste of coyote ammo if I shoot more than 3 at paper.

xdeano

 

[stumpm2]

In November I was at the range working uop a load with H1000 and I couldn't for the life of me get the speed up.
I am shooting a 28" Gaillard1-8 twist barrel built on a savage , the temperature was near freezing and I had a full load of h1000 behind berger 105's.

I tried everything to get the speed up more neck tension seated the bullets long ,fed,cci,win primers and the velocity was different with the primers.
So I got in the truck drove home got some different primers in LR magnum ,the speed climbed right up past 3200fps.

I use Hodgdon Retumbo in my 243 Ackley with Federal 215M Magnum primers with extreme spreads of less than 7 fps. I think the slow burning powder need a little more juice for consistent combustion.

 

[Scott Harris]

According to the Hodgdon website, a max load of H4831 in 243WIN is 41.0gr with 107SMKs. The Berger Hyubrids are 1.26" vs 1.23" for the SMKs. According to Whitley, the 6SLR has 1 gr less capacity than a 243WIN. Therefore, 43.5gr in a 6SLR would seem to be 2.5grains over a max safe load: conservatively. Am I missing something? For my part, I find between 41.0 and 42.0 of H4831sc is a max load in 243win. I was getting about 10 reloads at 42.0 grains before the primer pockest on Lapua brass get really loose. So, I've backed off to 41.2gr to get 20 reloads....in 243WIN with 105 Hornady A-Max. I don't understand how you can get 43.5gr with a smaller case and longer bullet. Long throat?

 

[xdeano]

I tried the 43.5g of H4831sc in mine, there was no pressure signs at all. The case still had a pile more room left in it.

That's like the H1000 that i'm shooting, I called Hodgdon to get the specs for it in a 243win case just to base line, they said max of 46.0g Compressed and i'm shooting 47.4g Compressed, with no pressure signs at all. I've gone up to 48.5g with no problems.

xdeano

 

[xdeano]

with my case loaded into quick load at 43.5g H4831sc the case is 95.2% full. It's 100% full at 45.7grains. It's showing a node for my barrel at 44.4g and 47.6g. I wouldn't use these numbers for your own guns though as it's just a computer model and it could be different for your guns.

My water capacity is 54.35g. with winchester brass, so not quite a grain less, in my case. Others may be different. These numbers are based off a physical weight and a computer calculated weight. Both came up with the same answer.

xdeano

 

[xdeano]

Here is the numbers from Hodgdon for a 243win with a 105-108g bullet.

H1000 43.0g-46.0gC
H4831sc 38.0-41.0

These numbers are lawyer proof. So going above these numbers is fine if you're watching for your pressure signs.

xdeano

 

[Julien]

I noticed some of you guys have done the same thing as me and have been able to put more powder
in a SLR than what hdgdon recomends for a 243. Maybe the 30 degree shoulder of the slr has something to do with the pressures staying low.

My 243 cant handle as much of the same powder as my SLR maybe it has to do with the shoulder angle maybe not.

 

[Trevor60]

Is everyone single feeding these rounds I am looking at either the 6slr or 6cm for tactical matches and am curious if anyone is mag feeding these round anyone have any issues.

Thanks and sorry for deviating from the original point of the thread
Trevor

 

[xdeano]

I'm mag feeding mine. I'm went with the short throated reamer for the 105 class bullets. I'm using the Berger 105 hunting vld and i'm just setting to mag length and jumping them. They work just fine. Picked up a group the other morning at .114" they shoot just fine. I'm not shooting a bench gun either, just a hunting rig with a med palma barrel, not to heavy, it's one of my coyote rigs.

xdeano

 

[kyreloader]

A quick follow-up. I had fifty more cases that I wanted to shoot to fireform and also to shoot an OAL test again. This time I started at 5 off and shot 10, 15, 20, 25 off at 300 yards. I again planned on shooting two 5 shot groups with each seating depth and seeing which depth shot best. I planned to compare those results to my previous test and use the best depth for my OAL.

I started with 5 thou off at 300 yards and I had a nice cluster that shot under 1/2 MOA. I decided to shoot the 10 thou group next, again less than 1/2 MOA. I proceeded to shoot the next three seating depths and all but the 25 thous group was under 1/2 MOA at 300 yards. I was shooting prone with front/back rest, so was unable to chrony my loads.

Since all seating depths were shooting well and I was not really making any headway for the best OAL for the Hybrids in my barrel, I decided to shoot at 600 yards the rest of the seating depths (5 shots at each seating depth). I planned on using the seating depth with the best vertical at 600 yards as my seating depth. By this time, the winds were up a little more, making the shooting more challenging. Both the 15 and 20 thou seating depth had less than 1/2 MOA vertical at 600 yards, with 10 off just over. Therefore, I plan on using 12 or 13 thous off the lands as my load. That way, as my throat lengthens, I will still be in my sweet spot for the OAL.

I want to give kudos to Berger with this bullet, in my rifle, it seems not to care how far from the lands I shoot it.

My plan now is to bump the shoulders back 1-2 thou, sort for neck thickness(turn if necessary), load some up and shoot at 600 yards in a match at the current load. If results are satisfactory, I likely will not mess with powder charge and use the barrel life to shoot club/practice matches.

I continue to like the 6SLR so far.