Ok here's my Dilema, gonna try some .270 cal.

[Petro58]

Still fairly new to casting, I've had success with my handgun loads and figured I'd try some things for a Browning BAR in .270. Wow the Manuals I have Loads Suck, and are inconsistent. Very few with OAL's and powder charge inconsistencies. Ok I'd appreciate anything you all could share to give me an Idea based on your experiences with the .270, and the Components I have. Any Ideas which way you'd start? Or a different Powder and Start. Not Looking for your specific, unless you just want to share. But Powders that maybe you tried that didn't perform as well as expected. Or what powder worked better. Maybe I need better books for my Rifle Loads?

Thanks In Advance

Browning BAR Mark I .270 caliber
Universal neck expander
Brass Win, Fed, Frontier Rem. All brass has been FL sized, also have a Neck Sizer
Primers Win Large Rifle and CCI 200 Large Rifle.
My Boolits should be Lyman#2 hardness (or Close)
Lee Mold # C277-135rf, average wt 136.2gr, Powder Coated, Gas Checked, sized at .278
My OAL. Inserting dummy cartridges into the chamber, appear to hit the lands at a Length of 3.22 so I'm figuring 3.12 or there about.
Powders Listed are Powders I have on hand.
Varget
4064
4198
4227
4350
3031
2400
Herco
Unique

Lyman's Cast Manual #3 *** the most useful so Far
mold #280412- 136gr
OAL 3.095
Unique Start 11.5 Max 14.8
Herco 12.0 15.0
IMR 3031 29.2 40.0

Lyman #47 Nadda

Lyman #48 Nadda

Lyman #44
Mold #280412- 136gr
No OAL
Unique Start 8.0 Max 12 **Big Difference?** seems to me
No Herco Listed
No IMR3031 Listed
2400 15.0 23.0
IMR4227 15.0 25.0
IMR4198 20.0 28.0

[C. Latch]

I've never cast for a .270 or any other semi-auto rifle (I don't shoot semi-auto rifles enough to justify it) but I would guess that it's going to be difficult to get the rifle to function with any of those powders except possibly the max 3031 load.

YMMV.

[chutesnreloads]

How do you intend to use this rifle with cast boolits?Hunting?Plinking?Targets?

[Petro58]

All 3 would probably qualify. Shooting Steels at the Range and maybe Hunting. 'Yotes and average Deer in Ga as far as a Hunting Load.

[Wolfer]

I've never shot cast in my 270. If was going to I would start with the old standby. 16 gr of 2400 and work up until accuracy fell off. Accuracy will fall off long before you get into pressure problems. This is my opinion anyway.
When accuracy fell off I would take the next slowest powder and start with the gr that the 2400 failed at. As I see it this should be safe. Work up until accuracy falls off.

[aspangler]

Here is the load data I got from Reloaders Referance ( free on the net and good stuff.)

135 grain boolit
(all max loads. reduce 10% and work up)
700x 13 grains 1643fps
3031 30 grains 1998 fps
IMR4198 26grains 1994 fps
Red Dot 13.5 grains 1698fps
Reloader7 26 grains 1967fps
sr4759 23 grains 1956fps
Win 748 31 grains 2002 fps

Use the data at your own risk.

[Petro58]

Well darn, as Expected my Loads Failed to Cycle the Bolt 100%. Still going to try a couple other Powders. FYI I tried up to 14.5 grns Unique with No apparent movement of bolt, and up to 26.0 grns of IMR 4198, which 3/4 opened bolt. So I was close there, No apparent overpressure signs, ie. case imperfections, flat primers, primers backing out etc. So back to the Drawing Board. I have a manual that shows IMR 3031 loads maybe I'll try a lader with it and maybe get some 4895. And of course might as well try some 2400.

[Digital Dan]

You might think about taking a look at the Hodgdon web site for load data. They list a fair number of loads with you bullet weight that hover around the 40 KPSI realm.

[Harter66]

Well probably apples and oranges, but here goes.

With the 6.8 Remington it's a half scale cousin that shares the lightest bullets. In the AR (more bananas) it takes nearly jacketed start loads of nominal jacketed powders to get good function. I know this goes against the normal right way to shoot cast but it is what works for me in 3 rifles.

[Moonie]

My 6.8 cycles just fine with intermediate length gas 18" Bison barrel, 134gr Ideal boolit and 18gr H4895. In fact I have found H4895 has great gas volume to cycle gas operated semi's. I have a son with a 742 in 30-06 and we shoot 170gr Lee with 35gr of h4895 and it cycles perfectly and shoots well.

[Scharfschuetze]

Well darn, as Expected my Loads Failed to Cycle the Bolt 100%.

That is to be expected. The balancing act of getting a semi-auto to shoot both accurately and reliably with cast boolits is quite a challenge and often it is never met, depending on the rifle. I have no experience with the BAR other than shooting one in 338 Magnum on an elk hunt once, so my guess is worth about what it takes to buy a cup of coffee at the diner.

My 270 is an old Pre-War Model 70 so I have no loads that might work in your gas gun as my load are fairly mild in deference to its Weaver 330 scope of equal seniority as the rifle.

My guess for your gas gun? Well, it's going to be all about port pressure as well as a mild enough pressure not to damage your boolit. Your Varget and 4064 powders or their equivalent would be what I would start off with to meet your goal. I would also get a heavier boolit, say 150 grains so that you can get that port pressure up without exceeding the strength of you alloy. The 150 grain RCBS 270-150-SP is the mould that I have for the 270.

Whatever powder you decide on, it should hold its pressure curve longer and further down the barrel in order to bleed that pressure into your gas cylinder. While I can't find any load data for cast boolits for Varget or 4064 in my manuals, I tend to think that a starting load of 30 grains with either would be safe with your boolit weight. Load five of each starting at 30 grains and work up following the usual procedures until you get (hopefully) to where you enjoy both function and accuracy.

Remember that your BAR was designed to function with cartridges generating about 50,000 CUP chamber pressure. That's just not something you're going to achieve with cast boolts so try and fool your gas system with a slower burning powder behind your lead projectiles. My bet is that you'll get there with the Varget powder.

I use a non-canister powder similar to 4895/4064 in my M1 Garand rifles with perfect function and accuracy. While they are 30 calibre, I go with the heavy boolit and medium powder formula for them with perfect success. Some members here use 4350 and 4831 powders with good success in their M1 Garands with cast boolits which supports the theory that slower powder is better in gas guns.

[JWT]

My 270 is an old Pre-War Model 70 so I have no loads that might work in your gas gun as my load are fairly mild in deference to its Weaver 330 scope of equal seniority as the rifle.

What load do you use in your model 70? I'm going to be loading a NOE 160gr in my Steyr Mannlicher 1950 model.

[Scharfschuetze]

JWT,

I've had great results using IMR 4198 and the 150 grain boolit. Try 20 grains for about 1,800 fps.

Another good powder is SR 4759 (if you can still find it). 20 grains of it will also put you in the neighborhood of 1,800 fps.

Yes, I'm stuck on 1,800 fps for almost all of my Ought-Sixes and the 270. That velocity just seems to be a sweet spot for me.

I don't think these loads would do generate enough port pressure for the OP's BAR, but he could try them.

Just got a love old 270 Winchesters.

[BCB]

I too am a fan of the .270 Winchester—got 4 of them and 1 I have dedicated to cast. It is a Model 700 Remington that I won in a gun raffle. My Model 70’s are older ones and they have shot nothing but jacketed since the 60’s…

Regardless, I use the 287346 (a 0.284” slug sized down to 0.278”), the 280642 and the NOE 279-124-FP…

The 287346 and 5744 for a velocity of around 1810 fps…

The 280642 and 5744 for a velocity of around 1667 fps…

The 279-124-FP and 5744 for a velocity of around 1714 fps…

Other powders used with good accuracy were Trail Boss producing less than 1400 fps with the boolits used and Unique which produced 1749 fps with the 279-124-FP boolit…

As mentioned by another poster, I also did not get very good accuracy when I went over the 1800 fps mark. I tried up to 2200 fps, but accuracy was mostly mediocre at best…

Again, these are loads shot from as bolt rifle and not a semi—no experience with them and this the .277” cartridges…

By the way, the 279-124-FP from a T/C Carbine in 6.8 SPC shoots extremely well using 10x and IMR-7383…

And finally, Petro58, if you got that data I sent you—You are Welcome…

Good-luck…BCB

[Duckdog]

I've just started casting for a 270 NEF with the Lee 135 GR boolit and have had downright excellent results with 14 gr of Unique. Granted, it's a single shot, so I don't have to worry about cycling the action. It's been to cold to set up the chrony, but I'll get to it to see what that load is shooting at.

The 270 was the last caliber that I have that I wasn't casting for, and I'm wondering why I waited so long.

[Petro58]

Thanks for all the Input from everyone. I haven't given up YET, and my intent is to go to Slower Powders and try some loads there and see if I can get the Bolt to Cycle and go from there. I've got Varget, H4895, IMR4064, IMR4350 I'll try all of these and see where things go. DR.'s appt. Thursday having some issues maybe some scary stuff, maybe Nothing. Again I appreciate all, and will let you all know how my loads work out.

[Petro58]

Scary stuff, I've appreciated everyone's input into this project. But I may have to move it to the back burner for awhile. Go into surgery March 7th possible Cancer. If it is they'll try and remove it without Spreading it, but they won't know until they get in to see. I have several Ladders built, with a couple different powders, just haven't had the chance to get to the Range. Hopefully all goes well and I can get to Range to try these ladders out.

[Harter66]

Petro
You have my best hopes for you.

[Scharfschuetze]

Yes, God's speed with your surgery and recovery.

[whisler]

Prayers for your recovery!