6.5x55 velocity

I'm having trouble developing a load for my 6.5x55, I am after a bit more velocity I believe I am only getting around 2500 fps and am already getting stiff bolt lift and extractor marks if I go up .5grain. The rifle is a ruger m77 with 22inch barrel I would have thought 2750 should be well within reach. This velocity is figured from what the books say I should be getting with the powder charge and from a proven trajectory. Crony is on the Xmas list.
The load is 140gr sst, 41grns AR2209 this is well under book max, I have three areas I'm looking at.

I seam to get really dirty necks, I have heard this can be from underloading which doesn't seam to make sense, I'm just a bit confused by this if the brass is showing max preassure surely the necks should be sealing.

The brass is PPU so it may be a low quality, as said I'm getting stiff bolt lift and extractor marks but I would have thought even soft brass should handle his load comfortably. I have got a batch of hornady brass left over from a couple of boxes of superformance I could try.

The seating depth, currently I have a .1mm jump to the lands, I am wondering if this is to close and causing some preassure spike.

My question for you is what would you try first change the brass or lower the COAL?
If I change brass or COAL do i need to lower the charge weight and work back up and by how much?

Thanks every one.

I would change the coal first. Although I muck around with a couple of cg's the load you are using is below what I am currently at. I too use the 140 sst; ok pill as I see it. Currently I am generating about 2600's with the sporting version of my 6.5. Coal is 2.990 but I am going to extend it to 3.1. Various forums suggest the 'variation in throat length' whilst others say '6.5 likes some jump...'. That said I am thinking older actions. I've had no issues with PPU brass, but perhaps you could weigh a selection of individual cases to see if they are the same. My 2 cents worth from an old dude with time to play round.

I had a good run with Highland brass which I am informed is the same manufacturer as PPU. Mine likes 42.4gr of 2209 behind a 140gr SP so I do not think it is the charge itself. I would try seating the bullet deeper giving you a shorter OAL. I think from memory mine is about 2.9 but I will check later today.

I have had a few 6.5x55's over the years I got better velocity and accuracy with 2213sc, 0.1mm is way to close to the rifling it would explain your high pressure,
Hornady recommended C.O.A.L at 2.905" start there to get the powder charge sorted first before mucking about with the seating depth

I'm using that brass in 3 of my 6.5s havnt had those problems and ive gone as far as 45gr using 2209 my scientific way of setting up the seating depth is start a projectile in a necksized case without a primer then put it in the rifle and close the bolt open it and take the case out put it in your press wind the seating die out and raise the ram then I wind the seater down till it touches the projectile lower the ram then wind die down 1/4 of a turn then that's it its worked in all the calibers I reload for one exeption is the m96/38s I reload for they have long throats so I seat 6.5mm of projectile into the case you can keep the case you just used for setting up/checking seating die I don't have all the indepth measurements etc just a target to show it works

how do you know what velocity your getting

I have used the same method as Northdude and it works. Word of warning though as dumb ass me thought 'one size fits all'. Duh! Loaded a few (single figures) and they fitted my sporterised 6.5 with smooth bolt closure. Thought I would chamber one in my fully wooded/ shooting prize/ beautiful specimen and could not close the bolt. Read on an overseas forum that some "better" were refurbished at sometime. Mine could be one.

I'm at 46.3 using 140 and no signs of pressure although slight cratering on primer.
This appears well out of my league I'm sorry but I'd definitely bump the projectile back by a half a mm and try that.


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I'm running 46.5gr of 2209 with a 143gr eldx in Lapua brass. 2780 fps from 22" T3.

My oal is 3.203" and is off the lands.

I'd try seating a tad deeper. Say 20 thou (.5mm) off lands and see how that goes.

My load is reasonably accurate in my t3

Attachment 71837 but every rifle is different

With my .243 I've had pressure problems PPU/Privi cases. Rem & Win are ok.

Good tip there on OAL setting Northdude for those that don't have an OAL gauge.
My rifles are from 20 to 40thou off lands apart from a military throated Swede which is nowhere near the lands.
Moderate loads in all.

How far did you check your trajectory to arrive at that speed? It is possible your speed(and pressure) is a lot higher than what the book says especially if loading close to the lands.

Thanks every one for the responses,
sounds like the seating depth is where I should be starting, when I first setup the load i did the bullet in chamber with slight preassure and cleaning rod down barrel, and did the lose neck thing to confirm where the lands were, so I'm confident of thos measurements, just set my load up to close by the sound of it.

I only shot to 400 to confirm that velocity but the bullet was dropping allot more than the ballistics calculator was saying for a velocity of 2700.

I need to load some more up any way so do I need to back the load off at all seating deeper or just stick with the same and alter the seating depth.

Also as @veitnamcam said if the preassure and velocity are higher because of close seating depth is this a better way of achieving velocity or seating deeper and using more powder? This isn't something I even new existed with reloading (I am fairly new to it) I thought seating depth only changed accuracy.

The accuracy is spot on averaging around .75-1 inch off a good solid rest so I am hesitant to change things but I got into reloading to try get the most out of this case and I might as well be shooting the factory loads at thos velocities, I'm trying to shoot longer ranges.

Thanks again.

Also might have to bump that cronograph up the priority list

Potentially so much going on there...is the zero right...are the clicks on the scope accurate...my Bushnell elite is miles out...way over 1/4 inch for each click....I start a scope by shooting a three shot at 100 yards then dialling 12moa and seeing how much the group rises. My Lee scales I used for years tuned out to be about 2 grains out as well...I'm still using cheap gear...and it makes life complicated.

Hey Rusl, great you have access to a decent range. 2500fps would be commensurate with 41gr of 2209 I would think.
I would do as shooternz recommends and start at known data book COAL and work it up.
Measuring chamber length by closing a inert case in will give a few thou jammed in the lands reading and also I found I needed to repeat the measurement several times to get a 'true read'
I think I was at 45.5gr 2209 with 143eld. Running 120gr now.

Set a case up how I described and compare it to one of yours start with the simple stuff first also have you worked up to your load or is it the first one you've tried

Yea i worked up to this load, I have measured coal again and was bang on I'm just loading up some new rounds now with the seating depth quarter turn in from lands like north dude suggested which is about .3mm shorter than before, should put me .35mm off lands.
Thanks hopefully if the weather holds I will get some testing done one day this week and will post results.

One full turn on standard 14 TPI dies will give you ~1.8mm change, so 1/4 will be ~0.45mm. For your situation I would start at 0.5mm (20 thou) off jam so 1/4 turn is as near as damn it is to swearing.

Hi Rusl, in the interests of eliminating some obvious possibilities you haven't mentioned to what extent the cases are being sized prior to reloading; can we assume that the cases don't start out tight to chamber, and also that the case length is within the maximum spec so there is no chance of excessively long necks jamming the bullets when chambered ? There is also the possibility of embedded carbon build up in the throat & neck area resulting in much the same effect - worth checking for.

Also mate don't bother with the chrony, just get zero spot on and head out to 3-400 odd and shoot a group without dialling or holding over (be sure to have a target set up to take 12-24 ish inches of drop so a tall target). Measure the drop in inches or mm if you are a MIL guy and feed speeds into an app until the drop matches. Far more accurate than the lower end chronys.

Heaps of good info coming in here thanks, I'm pretty sure the chamber is clean as I did wonder if it might be somthing like oil or solvent in there so gave it a good clean out initially.
Brass is fired only in this gun and neck sized and trimmed with a lee trimmer with mandril that sets the length, also I randomly measure cases as I do it. Loaded rounds slide in with ease no stiff bolt closing etc.
Thanks gibo about the tip for working out velocity, that's how I did it to get the numbers I have, I used a left over sheet of gib board from a building site nice and big, but I was starting to think I may have been on the wrong track and a crony was the ticket. But I would way rather spend the $ on practice bullets, I hope once I have a nice load setup I shouldnt need to alter it again therefore the cronograph would sit with all the other stuff I have bought over the years and never use.

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Originally Posted by rusl

Heaps of good info coming in here thanks, I'm pretty sure the chamber is clean as I did wonder if it might be somthing like oil or solvent in there so gave it a good clean out initially.
Brass is fired only in this gun and neck sized and trimmed with a lee trimmer with mandril that sets the length, also I randomly measure cases as I do it. Loaded rounds slide in with ease no stiff bolt closing etc.
Thanks gibo about the tip for working out velocity, that's how I did it to get the numbers I have, I used a left over sheet of gib board from a building site nice and big, but I was starting to think I may have been on the wrong track and a crony was the ticket. But I would way rather spend the $ on practice bullets, I hope once I have a nice load setup I shouldnt need to alter it again therefore the cronograph would sit with all the other stuff I have bought over the years and never use.

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Measured bullet drop at a 'known' range dont lie mate :D

also are you using an accurate g7 bc ie litz ?
some manufacturer bcs can be optimistic

As you have some Hornady brass, try it. I don't see the powder charge or CoL being the issue here.

I can load a couple of pills up that are very safe [emoji41] in Lapua brass And you can do a ladder test. Where in NZ are ya or are you in Nicaragua?


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Up in northland not quite Nicaragua mate, I have loaded a handfull up with a shorter coal and will try this first, I was trying to save the hornady brass for a eld-m load once I get a bit better and start shooting further. I was going off the hornady bc I will investigate this aspect further. cheers

Something else you can try, measure the grains of water from a case fired (but not resized) from your rifle. You have to have it full to the top of the case, tap it to raise any air bubbles and square across the mouth, doing it 2 or 3 times ans averaging the result is best. Send me the result and I'll feed it into Quickload, sometimes that will tell a story (and sometimes not).

Cheers

one other thing no one has asked yet.....are you 100% positive its 400 yards and not 410 or 390?????

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Originally Posted by Micky Duck

one other thing no one has asked yet.....are you 100% positive its 400 yards and not 410 or 390?????

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I mentioned 'known range' in post 23 :D

Slug your bore I have a tight 270 that does this to factory ammo.

Attachment 72042

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Originally Posted by Gibo

I mentioned 'known range' in post 23 :D

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my bad.......

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Originally Posted by Micky Duck

my bad.......

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Nah no way :D