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Just goes to show, primers and brass aren’t always a good indication of pressure signs. Pretty amazing but also bloody dangerous considering they didn’t get a sticky bolt even way way above the pressure maximum for the cartridge.
https://youtu.be/uXkmcpk7Brc?si=fHSwc-BghGkyYBHQ
That's impressive, a little crazy but impressive all the same.
Im not into reloadig but that was impressive.A well built 308 thats for sure matching a 300wm.
Those 300wm speeds are definitely low. Is there a hand loader on this forum that doesn’t get over 3000fps with that weight pill?
Still it’s impressive velocities. As they say often, don’t try this at home. That entire setup is way over spec.
Greetings All,
I have seen this happen before. Load worked up gazing at primers and such based on some extra hot loads for a wildcat rifle, no longer published. No "pressure signs" but the cases looked fine but were stuffed with expanded primer pockets. One of the reasons I work up loads using the chronograph. We have mostly heard the wails of "but there no pressure signs" over a now defunct rifle or buggered cases.
Regards Grandpamac.
Noone is suggesting you should work up to these sort of speeds or pressure, just showing what could be done with heavily over spec builds with custom minute tolerance chamber reaming and the right brass/primer combination.Quote:
Originally Posted by grandpamac
Not at all in the video was it suggested that anyone should try this, in fact it was heavily advised repeatedly that you don't.
Cool video, but yeah nah not advocates for over pressure loads.
Greetings @dannyb,Quote:
Originally Posted by dannyb
I did note on the video that they were using velocity to validate or correct pressure same as I do. The difference is that I use pressure tested data for the cartridge rather than Quickload which I don't have. I also spotted that they were using Alpha cases with small rifle primers. First I have heard of Alpha which I assume is a premium brand and likely harder in the head than your average brass so there is a big variable. Their point and mine was looking at case heads and primers to divine pressure is worse than worthless for working up loads and only reliable data is worth using validated by the chronograph.
Some handloaders still rely on the old and worthless pressure signs and it is them that are likely to come unstuck.
Regards Grandpamac.
Sorry if my reply sounded preachy, it wasn't intended :thumbsup:
No problem. Sometimes my brain gets ahead of my fingers so my meaning is not clear. I had not watched the vid so went back and watched most of it, something I likely should have done first.Quote:
Originally Posted by dannyb
I have found the chronograph absolutely essential in handloading and found the continued reliance on pressure signs by some frustrating. Hopefully the arrival of the Garmin chronographs, reasonably affordable and easy to use will change that. At a price of under $1,200.00 or about a that of a half decent scope more will make the change. My 35P cost $850.00 ( a decent rifle and scope then) over 30 years ago when few had chronographs. I rang up a friend and told him I had bought one. He rang back a short time later to check he hadn't dreamed it.
Regards Grandpamac.
well seen as though I appear to use old and worthless methods I shall reply in kind...if your not hot rodding and trying to get silly speed by stoking up cartridges above what manuals say is ok...you DONT NEED AN EXPENSIVE BIT OF KIT to tell you it goes bang and hits what its aiming at,and does so safely.
Not sure it was a responsible thing of him to post. You just know there's going to be someone that ignores the warnings, takes it out of context, and decides they should try to unleash their off-the-shelf 308's inner magnum.
Well said @Micky Duck,Quote:
Originally Posted by Micky Duck
From reading your posts including the above you are not the type of person to work up from max. You start low and work up to a medium level that works for you (and would work for everyone else as well if truth be known). For you the handloading is a prelude to the main event of hunting. For some of us older chaps the handloading is the main event garnished with a bit of target shooting plus the odd armed grandpa walk seldom requiring any loud noises to be made or anything heavy to be carried.
Best Regards Grandpamac.
Kinda agree, but they were very very clear a lot of precision work went into this and it wasn't just a slap together and load her up as much as you can.Quote:
Originally Posted by Pommy
They also gave multiple warnings on not to try this at home, what more can you do ?
Posted or not there will always be someone who thinks they are invincible and that book max is only a guideline for sheep.
I have a friend like this and I refuse to shoot his loads or rifles, and yes I have told him multiple times I think he's playing with fire :psychotic:
there is/was a new type of case being bandied around about a year ago..special forces round in 6.8mm ??? has steel head and brass body to withstand much higher pressure than normal. the technology is there to do the high pressure thing,Ive always thought a thick walled case was a feasable idea,sort of take the belt on likes of 7mm magnum all the way from head to shoulder to enclose the bit that stretches /gives out.
@grandpamac
Have a look at gordons reloading tool, if you are missing quickload. Its a free (and better!) alternative
Greetings,Quote:
Originally Posted by Micky Duck
It was introduced as the 6.8 or .270 Fury as a military and later commercial cartridge. About the size of a 7mm-08 but with .270 Win or better performance. The steel head cases came out in the US about 50 years ago.
GPM.
So..,steel cases,like what Barnaul etc use,how do they stack up as a single use item,as so far as handling excess pressure??
Yrs ago i was in a shooting compitition,north canterbury.We started at 100yds to make sure our rifles were on song.Guy 2 mtrs along from me had a 270 with some new reloads he was trying out.His second shot gave a loud explosive bang,his head flew back about 1/2 a metre,blood and smoke off his face.The bolt was blowen back with bits missing,scope had a few marks on it.Lucky he was wearing shooing glassess.Officials came running over to him,with 1st aid.Rifle was buggered for a while but he keeped his eye sight.
A extra fps just ain't worth it :thumbsup:Quote:
Originally Posted by Trout
The entire video should have an annoying watermark or scrolling text saying "I am an idiot with money and a lathe. Don't replicate anything I do unless you want to die".
I joke with a mate of mine that his channel shouldn't be called "Ultimate Reloader". It should be "average reloader with cool toys".
Yes SIG have released the 277 fury rifle and cartridge. It has been SAAMI spec'd at 80,000psi,
Yes it is a composit case, steel & brass with alloy as well.
QL pressure I take is an estimated pressure from the Quick Load tables.
How were they getting the corrected pressure number?
Think they were using the QL velocity vs actual velocity and taking that percentage difference and applying it to the QL pressure estimate.Quote:
Originally Posted by Lauries Hut
Classic ... as always. 1 grain under maxi is the sweet spot. Not sexy but oh so reliable and accurate.Quote:
Originally Posted by Micky Duck
Greetings @Lauries Hut,Quote:
Originally Posted by Lauries Hut
The relationship between velocity and pressure is quite linear as it is between powder charge (for the same powder) and velocity. This can be demonstrated with the Hodgdon load tables and a pocket calculator or a graph. I use the same methods but I am looking for a safe load at less than maximum pressure where the vid was demonstrating the fallacy of working up using pressure signs. For many cartridges the book data is right on the button once barrel length has been factored in. Some powders and some projectiles give quite different results due to a change in powder speed or projectile construction. I differ from some in I prefer to base loads on published and pressure tested data rather than Quickload which is an estimate based on case capacity. Correcting a velocity based on an estimate is still an estimate.
Regards Grandpamac.
+1 for Gordons Reloading tool. I’m trying to work up a 308 load which has no book value for, and I’ve used it for a baseline to understand pressures and where to find the limit. Ironically my real life chronograph figures are lower than predicted from the application, but it still a good place to be to understand where to stop. (Currently sending a 185gr D46 @ 2750fps)
I’d watched the UR video and did wonder how many people would replicate it without the basic understandings. I cringe when I talk to some handloaders that just load based on the group on target at 50-100M, without measuring speed or looking up pressure max.
I thought it was a stupid video, and only told everyone hat they already knew. That 308 was 300-400fps slower than 300wm unless you make a dangerously high pressure load.
I thought perhaps they were going to try RL17 or Rl26 or some other exocitic(ish) powder to try squeeze maximum performance form the 308 case.
But once I saw they were using Varget I skipped to the end as I knew what the conclusion was going to be.