Anybody load for semi-automatics ,Browning

[James Jones]

I got a buddy that has just bought a Browning BAR
short trac in 270WSM and hes wanting me to work up some loads for it , hes wanting to shoot 140gr bullets out of it as fast as possible but I don't know how to go about dealing with the pressure signs in the autos are they the same as bolt guns or will one start to see problems with the gun before pressure signs show up.
I'm planing to use 4831SC as athe powder and 140Gr Nosler BT's
Any help would be appercisted

 

[kraky2]

I'm not going to tell you I'm an expert but here goes some of my experience and "hearsay" from the forums. Some people say don't go any faster than I4350 in a bar. Others have said that's now a wives tail that they handle powders right up to re22. I've loaded for my bar and have used slow powders and never had a jam or any damage that I know of.
I can say this for sure. My buddy just got one in 7wsm. We went to the range with some nosler factory 160 pars and I was thinking with an auto and most likely mild factory loaded ammo we'll be lucky to see 2800 fps. It came out doing a whopping 3060 fps. WOW--that ammo is loaded warm.

My suggestion to him when he starts loading is to use loads around 4350 powder charges and chrono up and see where he stands against that factory charge while watching for pressure signs. (I'll be watching over his headspacing to watch for false signs like extractor rings and stretching cracks.)

I would recomend to you that you chrono your buddy's ammo and do the same. Maybe pull down a bullet and weigh the powder to get a guestimate of the burn rate.

These WSM's aren't fooling around for speed....and the pressure must be there to make the speed....this will be a whole new ballgame for reloaders working with these suckers in auto's.

 

[gonehuntingagain]

In my experience loading for my Dad's 338WM BAR is that the gun will tell you what you need to know. Too low of a charge and it won't cycle/feed reliably - and the same thing happens when the charge is getting too high.

Comparing your loads to some factory loads is an excellent place to start.

 

[kraky2]

Just for "poops and giggles" when I got home I put some info into quickload. I don't have the newest version that might have the 7wsm in the library. So I just asked quickload "what pressure would I have to run in the 7mm mag with a 24" barrel to get 3050 fps out of a 160 partition."
It came back with 60,000 psi....I would assume that ammo we shot out of the wsm was darn near right on those pressures.
Definately not the kind of ammo you want laying in the sun on a 90 degree day before testing!! Once again....if someone thinks they can gain any velocity over and above what I saw in that factory ammo....good luck!

 

[sewwhat89]

I am shooting a 300 RSAUM, and have noticed the same findings you mentioned about factory loadings vs my handloads. 165 gr factory smoking at 3417 fps and the 180 gr NP factory loadings are coming out at 3200 fps out of a 26" barrel. I get 2978 fps with the 180s out of a 22" barrel. The closest I have come to duplicating the factory 180 load was using a stout charge of H4350 with 185 gr Berger VLDs and got up to 3070 fps. The 180s shoot sub MOA, and I am toying with the idea of pulling some of them and reloading the factory load with some 175 SMKs to see how they perform. jm2c

 

[kraky2]

Holy smokes.....those velocities are right on the heels of a 300 wby. You'd almost think they are barrowing technlogy/powder from the people making hornady and federal "light & Heavy Magnum" loads. I'm not totally up to date on the rem RSUAM but isn't it just slightly less case capacity than the 300wsm or about equal??

 

[marks]

Yes I own a 7mmWSM BAR and have shot a lot of Himalayan Thar with it with great success. Presently using 140gn Sierra pointed soft points with 66 gns ADI2213SC or 4831SC with good results. Have also tried 120gn Sierra PSP at 68gns 2213SC. Another reloader is running 70gn ADI2213SC with 140gn Sierra heads and getting 3320fps ( chrono) with no signs of pressure. I am working up my loads after his comments and data check.

Tried 100gn hollow point Sierra with 70gn ADI2209 ( 4350 equivalent) groups really well and higher than 140gn at 100 meter target. Really impressed with result not as good on bull thar which can really take a hit and run off with 270 but not with 7WSM.

Diod hear that adding a browning scew on harmonic balancer makes a difference to grouping also. Note my gun has tendency to go right on /during recoil with 100gn but left with 140gn - what is your experience.

Regularly shoot between 300-500 meters no problem, find need very good rest so recoil doesn't move gun round too much. Tried gun on red deer bullet goes in front or back and straight through them as light skinned animals seems to work best once 200+ meters away.

Keen to hear from anyone that has had good results with tightening up groupas and getting BAR to not move left or right at recoil stage. Does a muzzle brake assist this effect, note noise of 7mmWSM have ringing in left ear more pronouced then from days as Government culler with the NZ Forest service 1979/80. Used a .243 BAR with cutdown SLR magazine ( 12 shot) 2-7 Kharls scope and average of 1.1 rounds for season including target sighting etc. Note we were shooting between 650 to 700 animals a season so find few guns that are as good as BAR for hunting - thry are really consistently accurate even on shot 12.

Note also owned sako and sauer rifles so have a very good reference my .243 shot as good as both of these rifles group 3 rounds under 15mm at 100 meters factory ammo.

 

[James Jones]

Thanks for everybodies info , I have since talked withthis guy and explained to him that fast isin't always better and getting fast/hot loads in and auto is a bad way to go about it especialy with the Browning alloy reciever.
We ended up with a load of 58grs of R-19 under a 150gr Ballistic tip running 2850-ish FPS with accuracy in the 3/4moa range out to 400yds , the gun cycles perfect and he has shot two deer and one hog with it and all three animals died withing 30yds. Granted that this isin't realy any fatser than what the old 270 Win can be easly loaded to this is out of a 20" barrel semiauto so its realy fast handeling.
the Ballistic tips is a great bullet but I think guys run them to fast and when the range is short they end up with the bullet "blowing up" , this load has a long bullet traveling at a moderate speed , while expansion is very rapid the higher SD of the bullet helps to deliver good penitration

Marks
The BOSS system on the Brownings works very well for guys that don't reload as it lets you tune the barrel to the load you want to shoot , if you reload thats basicaly what your doing your just tuning the load to the barrel instead of vise versa. Now say that you want a certain bullet to travel at a certain speed , well then you reload to get that bullet at that velocity then you dial in the barrel to like it. If you want to try differant loads and tune at the same time then your just chasing your tail and wearing out you barrel.
If you want the BOSS system I highly recomend getting the CR version ,thats the one without the ports. The ported version works as a decient brake but the blast is nasty , the first time I shot one was in a 300 Win mag BAR safari , I shot it and thought that I blew the gun up or pierced a primer with all the gas and crap that hit me in the face.