Estimating 3000+ fps from 6.5 Swede

[CobraRed]

3/8/15 UPDATE:
Stapped on the MagetoSpeed today. Was pretty dead on with my previous estimations: 3040fps.

And 3150fps with my 6.5x55AI so far.





Previous Post
Theoretical max supersonic range of about 1700 yards!

With exact environment data from my last shooting trip to the range depending on the BC calculator I'm getting 3020-3030fps based on shooting at 0 vs 600 and 700 yards using a .299 G7 BC or .585 G1 BC.

Pretty stoked, was hoping for around 2950. It just so happened one of my upper node on recipe development grouped the best. Was getting plate splashes all touching each other at 600.

No case/neck separation/crack or excessive wear visible yet.

Running:

Norma Brass
Tula Primers
RL-22
140 Amax seated just onto the lands.

1991 Remington 700 in 6.5 Swedish
McGowen 28" 1:8.5 twist 1.20" to 1.00" barrel
Viper PST
My own machined monopod and bolt knob.
Birch Stock with aluminum chassis




Now I just need a chrono to be certain

[Gofasterdammit]

That seems a little too fast for a heavy 6.5 projectile. Might want to chrono that.

[Pthfndr]

That's really pushing the limit of the 6.5x55. When the weather gets hot that load could well be unsafe.

And really, there's no need to push it that fast. I got 2800 useable accurate rounds from my 6.5x55 at 2950 fps. At that point the throat started going. At 3600 rounds my Swedish Mauser was sending them faster

FWIW, when I first started working up loads I had 47gr of RL22 and it sent them at 3150. Accuracy was phenomenal, but the temp went from 60 in the morning to 85 in the afternoon and I could barely open the bolt without waiting a few minutes. Needless to say I backed down from that load.

[CobraRed]

That seems a little too fast for a heavy 6.5 projectile. Might want to chrono that.

It is fast, but not outside the realm for modern 6.5 swedes. A lot has changed since the mauser days.

That's really pushing the limit of the 6.5x55. When the weather gets hot that load could well be unsafe.

And really, there's no need to push it that fast. I got 2800 useable accurate rounds from my 6.5x55 at 2950 fps. At that point the throat started going. At 3600 rounds my Swedish Mauser was sending them faster

FWIW, when I first started working up loads I had 47gr of RL22 and it sent them at 3150. Accuracy was phenomenal, but the temp went from 60 in the morning to 85 in the afternoon and I could barely open the bolt without waiting a few minutes. Needless to say I backed down from that load.

It was 81 degrees out :/

San Diego aint no Tahoe

[LynnJr]

Hornady #26302 140 2.905 48.0 Re19 46.0 2683 2238 1.1
Hornady #26302 140 2.905 48.0 H4350 43.5 2613 2123 1.2
Hornady #26302 140 2.905 48.0 IMR7828SSC 47.5 2662 2203 1.1
Speer #1441 140 3.00 51.9 Re19 48.0 2742 2338 0.8
Speer #1441 140 3.00 51.9 H4350 46.0 2735 2326 1.0
Speer #1441 140 3.00 51.9 IMR7828SSC 50.0 2772 2389 0.7

[CobraRed]

Hornady #26302 140 2.905 48.0 Re19 46.0 2683 2238 1.1
Hornady #26302 140 2.905 48.0 H4350 43.5 2613 2123 1.2
Hornady #26302 140 2.905 48.0 IMR7828SSC 47.5 2662 2203 1.1
Speer #1441 140 3.00 51.9 Re19 48.0 2742 2338 0.8
Speer #1441 140 3.00 51.9 H4350 46.0 2735 2326 1.0
Speer #1441 140 3.00 51.9 IMR7828SSC 50.0 2772 2389 0.7

[Pthfndr]

My rifle is a Tikka 695, and at the time had a Tru-Flite 30" barrel with with relatively tight chamber. Barrel was chambered and installed by Mac Tilton.

And I wasn't load testing in Tahoe, but at the Sac Valley range - 200' ASL.

[CobraRed]

My rifle is a Tikka 695, and at the time had a Tru-Flite 30" barrel with with relatively tight chamber. Barrel was chambered and installed by Mac Tilton.

And I wasn't load testing in Tahoe, but at the Sac Valley range - 200' ASL.

Nice. Yeah, 3150 is insane fast. I wasn't aiming for 3000+, more like 2950, just my upper node grouped the best and happened to be a barrel burner. which I'm okay @ 2800 rounds out of a barrel - i'm surprised it would even get there.

[bubbapug1]

bring it up to Pendleton for a scored match to see how it does....

[russ69]

...My research has found that modern actions can and often do shoot the swede up to the max pressure for 30-06 which is 60k psi, which I am still almost 3 thousand under...

That sounds scary. What method are you using to measure pressure? You are up in proof load territory.

[huckberry668]

Almost all of the 6.5x55 published data were developed with consideration for the old Swedish Mauser surplus rifles to be safe. And most of them are taken from shorter than 28" barrels.

Your 28" barrel and bore quality also helped with the velocity numbers. I have a 26" 8" twist MeGowen on my Stevens 200 (Savage) action. I'll have to chrono it next time I shoot it.

It's always a good practice to follow the published load data but in the case of 6.5x55 I'd factor in the differences of old and new action strengths. Be very meticulous in your observation of pressure signs and easy does it.

My 308win 175SMK load shot out of my 24" FN A3G at 2720fps avg when all the published load data indicated it should be low 2600fps. I believe the extremely low friction of chromed and tighter bore helped with the velocity without higher chamber pressure.

[Pthfndr]

The fastest load Lapua/Vihtavouri lists for a modern 6.5x55 is 2887 with a 139gr Scenar.

http://www.lapua.com/en/products/reloading/vihtavuori-reloading-data/relodata/5/98

Depending on how "fast" your barrel runs 2950 could well be within reach with a safe accurate load. But anything in the mid 2800 range will give you much better barrel life.

[ar15barrels]

That sounds scary. You are up in proof load territory.

60,000 PSI is no problem in the 700 action with a 30-06 boltface.
Don't forget that there are magnum cartridges being run at 63,000 PSI in 700's when even LARGER boltfaces!

Nowhere near proof loads.
Proof loads are 70,000 PSI.

[stonefly-2]

" A lot has changed since the mauser days. "


oldschool baby!

[russ69]

...Nowhere near proof loads.
Proof loads are 70,000 PSI.

I agree that the Remington action can handle higher loads than the old Mauser but one web site says: "Military 6.5x55 ammunition was loaded to a pressure of 3200 ATM which converts to 47008psi. Proof loads developed between 4000 and 4500 ATM which converted (x14.69) give pressures of between 58,760psi and 66,000psi."
So it is at proof load pressure for that cartridge and boxes might need to be labeled as such to be on the safe side (I'm overly cautious). When they sell off all the guys stuff, some idiot might buy it for his old Mauser (it wouldn't be the first time).
Actually I was more curious how he was measuring pressure?