First build done!

[Anchor Zero Six]

Seems like I have been without a bolt rifle for an eternity. I'm finally back and happy to say I rolled my own this time and I'm more than a little giddy about it!

Specs:
-Rem 700LA trued and parkerized (started life as a 300WM PSS)
-PTG pinned recoil lug
-PTG spiral fluted bolt with Sako extractor and APA knob (parkerized the bolt and handle)
-APA LA DBM
-20" Rock 5R MTU fluted 30 cal barrel chambered in 308, threadded with blended thread protector finished in "Parker" colored duracoat
-Timney trigger set at 3.5 lbs (like em heavy)
-McMillan A5 adj cheek rest
-Seekins sling rail thingy

Not done yet I have a 338LM PTG bolt and raising funds for a barrel and better optic (need more power for the 338) and then it will be a switch barrel 308/338

And this thread would be worthless without a pic so here you go

http://i238.photobucket.com/albums/ff193/AnchorStation/DSC00890.jpg

Oh forgot to mention that I put it on a postage scale right after I finished it and it came in at 9 lbs 12 oz without any accessories or optic.

[n517rv]

Very nice!

[BCmJUnKie]

I hate you.


That is one purdy rifle.

That thing just looks like a caddy....Im "Drivin" a cavalier.

But it rides nice, know what I mean?

Congrats on your caddy man.

[FromMyColdDeadHand]

Really nice! Why did you decide to go LA instead of SA for the 308?

Is that a Vortex scope?

Let's see some groups!!!

[Anchor Zero Six]

Needed to use a long action for the 338 Lapua. I can use 300 win mag AI magazines to feed the 308's just need to tweak the mag lips a little but it works just fine. Brownells actually sells a tool to bend the lips and gives the specs for a variety of rounds. To convert from 308 to 338 all I need to do is put the barrel in a barrel vice and remove the action with an action wrench. Replace barrel mag and bolt and thats it. Going to fab a barrel vice that mount to my trucks receiver hitch.

Its a Loopy MK4 3.5-10x and actually what started this project. Dad scored a deal on a 300WM PSS with this scope for 1100.00 about 12 years ago. He never really liked the 300wm without a brake and the project snowballed. Now all thats left is the trigger, receiver and scope so all in all not a bad deal.

Cant wait to shoot this weekend. Literally just assembled it this evening after bedding it yesterday. Had to make another trip to the mill to clean up some marine-tex that goobered on me but it turned out better than I expected. All I can say if it dosnt shoot .5-.75 I'm gonna be really dissapointed considering the time and money I put into it...fingers crossed.

[Anchor Zero Six]

I just cant leave shit alone ;)

Went another direction and scrapped the 308/338 switch barrel idea and ended up punching out the chamber to 300WM. Yep a 20" 300WM!

Going to do some load work ups using the new Berger 230 OTM's, playing around with some numbers in JBM I think it will be a hell of a combination.

Using FGMM 190 SMK's I was pretty pleased with the results. I think with a higher mag optic and some load development it will shoot even better.

http://i238.photobucket.com/albums/ff193/AnchorStation/IMAG0111.jpg

Had several gropups that had overlapping holes but then I would bugger up one and screw up the group size (10x is a bit underpowered for this type of shooting IMO)

Bottom left was 6 rounds but I cant tell if the missing round was within the top or bottom group of two. Only has 39 rounds of FGMM or I would have shot more but there was no ammo to be found locally.

[Silent]

Did you put this together or did you have someone do the work for you? Looks great ENJOY IT!!!

[Anchor Zero Six]

I built it myself under the watchfull eye of a veteran smith. I measured everything twice and then asked him to verify before I took any cuts.

[orkan]

What kind of velocity you seeing with the various loads. Share data please!

[Anchor Zero Six]

I have not had the opportunity to clock it, live just outside Seattle and the chrono dosnt like the rain.

What I do have is a WAG (wild ass guess) of what I am projecting the results to be.

A user over on SH got the following results;

RWS brass
CCI250
COAL 3.560" (just touching lands)
Retumbo

71.0 gr = 2755 fps and 0.372 MOA, 7 fps ES
71.5 gr = 2779 fps and 0.598 MOA, 19 fps ES
72.0 gr = 2792 fps and 0.926 MOA, 24 fps ES, heavy bolt lift


Based off of his numbers I assumed a loss of 50 FPS for each inch and the above data was from a 25" 300WM 1/10 RHT so I deducted 250 fps from his best load of 2755 and ran them through JBM using the G1 figures.

At 2505 what I came up with was;

Subsonic at 1600 yds
Energy at 1K 1098 ft/lbs
-29 MOA at 1K

and for comparison here is a std 175 load

308 175 SMK @ 2650
Subsonic at 1100 yds
Energy at 1K 496 Ft/Lbs
-34 MOA

One of the guys on SH is talking with his buddy a guy by the name of Tubb whos some sort of BB gun champ or something and suposedly knows a little about shooting ;) anyways they have been testing the MK248 with 20 barrels and supressors and are compiling some data which I'm sure will be much more involved than my figures. They did say that my guess of 50 FPS for each inch is a bit high and 15-20 fps is more realistic so that just makes me even more optimistic.

Have the 230's in route, Virgin Lapua brass, FGMM match primers and a selection of powders to start with but it sounds like retumbo will be the ticket.

Stay tuned more to follow....

[orkan]

I'd have thought retumbo a little slow for that short of a barrel.

You try any H1000?

In any event, I'd be very interested in seeing your hard numbers through a good "proven" chrono.

[Anchor Zero Six]

I thought that as well but my train of thought is its a bit more consistant across various tem ranges from what I have been told.

Have a bit of experiance reloading for 308's but not belted magnums so there will be a learning curve.

Have 22,19,Var,H1000 and Retumbo on hand to choose from so I expect in there theres a powder that will get me there in a safe load.

[Anchor Zero Six]

OK guys here is an update with some chrono data to support.

I finaly got a chance to chrono some ammo today. I shot two 6 round strings of FGMM 190 at 360 ft elevation and 45 F temp.

From everything I could find this ammo should be around 2900 FPS from a 26" barrel. If anyone has info to the contrary please let me know.

Average of 12 rounds fired was 2788 FPS which is 112 FPS less than the specified 2900FPS from a 26" barrel. Highest FPS was 2805 and slowest was 2764 FPS so the difference there was 41 FPS which was a bit more than I expected from FGMM but I have seen worse before.

As this is factory ammo I think it would be easy to cook up a load that will regain the velocity and not exceed safe pressure limits.

I'm stocked up on retumbo, re22 and H1000 as well as Lapua brass and FGMM primers to load up the 190SMK and 230 OTM Bergers. Santa needs to hurry his fat ass up and bring me my new press!

So thus far I think everything is looking good and Im not seeing any real drawback to a 20" barrel. I will certinly agree that there is a benifit to using a longer barrel and not going to say this is as good of a choice for length but for my wants (shorter lighter with alot more ass down range than a 308) I think this is a viable option. I had my buddy fire some rounds so I could observe and yes its a loud SOB with the brake but I didnt notice an unusually large flash, there was certinly a flash but nothing abnormal for a brake.

A06

[orkan]

Interesting. What chrono was used, and has it been verified accurate?

[Anchor Zero Six]

Used a shooting chrony POS

Been consistant in the past they are just tempermental and not user friendly. One of the reasons for the delay in data has been lack of sunshine in the PNW. Chronos I have found work best with good lighting and yesterday was nice and sunny although cold as a well diggers ass.

[MOA]

Why not start with Re22? It should give better velocity than Retumbo and in my rifle gave better SD and ED. Also the best groups for me. have done this long enough to know that it might not work out that way for you, but was just a idea.

Best wishes on the load work up and GREAT looking rifle.

[Anchor Zero Six]

Reloader powders seem to be a bit temperature sensitive. Retumbo I hear is pretty consistant but I have never used it before. Guys are getting good results on the heavier projectiles with H1000.

My solution is to try all of them and see what works best for my needs and location. Powder by the pound is fairly cheap so no big investment to be concerned about as I can get just about anything in one pound size locally. When I get it figured out I'll buy in bulk and pony up the shipping/hazmat costs but for now I'm trying the sampler plate.

[Pappabear]

Cool Build, I have often wondered recently about building a 308 off a 300WM so I could load and shoot the bigger/longer 30 cal bullets. That dont fit into my stock Remmy 700.

Anyone done this before for this reason? Does this make sense?

[orkan]

Reloader powders seem to be a bit temperature sensitive.

You are correct on that. Reloader is complete dogshit in my AO where morning to afternoon temp swings can be upwards of 40 degrees. A load that is tuned in the morning, won't be in the afternoon.

Hodgdon extruded powders don't have that problem. I've run a LOT of retumbo in the 338 and it is very stable.

I'm enjoying reading your progress. I've often thought of a hot 30 cal with a short barrel like you are doing. Please keep up the objective testing! It's refreshing to see someone take the initiative and push the boundaries a bit.

[markm]

orkan...

What do you think of Pappabear's idea of a long action 308 to mag feed long loaded ammo?

Custom chamber a better idea??

[orkan]

orkan...

What do you think of Pappabear's idea of a long action 308 to mag feed long loaded ammo?

Custom chamber a better idea??

I guess I don't see the point. Anything with a throat that long isn't chambered right. (remington) Any custom barrel that is chambered by a competent smith will let you get into the lands from an AICS mag. My rounds have an OAL of just past 2.8" while being 10 thou off the lands.

In the case of subsonic ammo, an argument could be made for seating 208's or 220's way out there... but then I would counter the argument by pointing out that seating the bullet deeper to reduce internal case volume is better for subs.

So really, unless its a switch-barrel rig or you have plans to go to a long action cartridge... I see no point.

[markm]

Yep. We're both running our factory Rem barrels which have very long jumps.

Sounds like Pappabear should be fine when we rebarrel these things.