6.5 CM can’t get any velocity, opinions please
- Thread starter ta6ppc
- Start date
So I got some star line and Peterson brass the Peterson is small rifle primer as well. With 4350 it shows an ejector swipe at 40.3 grains with a oal of 2.790 with a Berger hybrid the velocity is 2650ish average.
I don’t think brass is going to correct anything, the star line brass is very nice and seems to be reasonably hard unlike the hornady brass.
I think I’ll ease into the gunsmith and see what he says..
Sounds like a plan, I got 13 loads on a batch of Hornady brass running 42.5gr of H4350 under 140gr hpbts (~2,770 fps) with no swipes, and H brass isn't known for its outstanding quality. Both my 20" and 24" Creeds run much faster than your rig, and when I do run into pressure, it almost always jives with my recorded velocities (except for RL26, that stuff is nuts). It sounds like a systemic problem, and patches and workarounds won't really solve that. Best to address the root of the problem early so you don't waste a lot of time and components trying to get it to act right.
What do you care what speed the round produces. Really accurate loads are what you are looking for.
Do you own a borescope? I am curious to know what the throat looks like. Carbon can cause pressure issues at less than max charges.
No I don’t own one, however I used to shoot benchrest and definitely know how and what a clean gun looks like, I use and alternate between butches, sweets, even wipe out occasionally also use isso paste with really good results. I doubt it’s a carbon ring especially I’m around maybe 300-350 rounds total..
velocity reall drops off around 600 yards, really wanna run to 800-1000 without it running out of gas.
I’ve tried the 120 amax, had some from years ago and surprisingly didn’t shoot all that well, I only had 200 of them so I didn’t spend time with trying to develop a load.
Frist of all.
All you guys that keep saying speed doesnt matter when your developing a load are just completely not taking advantage of this combos potentential. Your basically saying your got a 6.5creed but you gotta settle for grendel performance.
And why the hell would you like to shoot a castrated 6.5 creed. Speed is king and its the trade off for performance vs barrel life.
To the problem at hand, sounds like either a nasty carbon ring or a short freebore reamer was used. A chamber cast or a bore scope will tell you what's up.
All you guys that keep saying speed doesnt matter when your developing a load are just completely not taking advantage of this combos potentential. Your basically saying your got a 6.5creed but you gotta settle for grendel performance.
And why the hell would you like to shoot a castrated 6.5 creed. Speed is king and its the trade off for performance vs barrel life.
To the problem at hand, sounds like either a nasty carbon ring or a short freebore reamer was used. A chamber cast or a bore scope will tell you what's up.
I’d find someone local that has a borescope and look at it. It may not have a carbon build up, but one can develop in less than 200rounds. Especially If you don’t use bronze brushes in your cleaning regimen.
Leo Smith
Gold $$ Contributor
The Loads you mention are max for that 24 in barrel. My 24 in Howa SA 6.5 shoots perfectly with 39.6 gr of 4350 w/ 147 ELDs.. But i had to work my loads up to know that. I never worried about fps so much. Even better with A tips. Do the load work ups, and not just max powder capacity for max fps. You want 3000 fps. Use 120 gr.
I d personally back the bullet off the lands .020-.030 like previously mentioned and try some load / powder work ups BEFORE assuming gunsmith needs to check it. If you re jammed that far in the lands that could very well be giving you the pressure signs/brass swipe.
Yeah it might have a short throat but if you can shorten your COL enough to relieve the pressure might very well get it in the 2600-2650 FPS range and not a big difference from a more standard 2700 FPS rifle. BC, BC, BC !! And as others said accuracy at a reasonable velocity will trump more velocity and a bad shooter !
keep us posted and good luck.
Yeah it might have a short throat but if you can shorten your COL enough to relieve the pressure might very well get it in the 2600-2650 FPS range and not a big difference from a more standard 2700 FPS rifle. BC, BC, BC !! And as others said accuracy at a reasonable velocity will trump more velocity and a bad shooter !
keep us posted and good luck.
Might think about, having your Gunsmith Ream out / reset Bbl to,.. a 6.5 SLR !
With a better Freebore for, the 140- 142 grain bullets at,.. 2,850 - 2,900 FPS
With a better Freebore for, the 140- 142 grain bullets at,.. 2,850 - 2,900 FPS
first thing i would do is get a bore scope and look at the throat... if your scratching the sharpie marks off on the bearing surface chances are you have a carbon ring issue ... which will cause pressure problems ... and you wont get a true measurement to the lands because the bullet is stoping before its getting to the lands... you can take some good carbon cleaner and let it soak for a bit in the throat area... then take a bronze brush on a short section of cleaning rod and chuck it up in the drill and spin it in the throat area.... you dont want to spin it up in the rifling but you can feel when it touches the lands.... im guessing you clean that throat up you will get a longer oal reading to the lands...
I have had a few custom rifles built. Field work no bench games. I always decided on the bullet weight and style before building the rifle. That way even if I changed bullet style it was a minor adjustment to keep it off the lands. I'd make up a couple dummy rounds and a box of factory if available and give them to the smith. With custom projectile weights there are never any proper factory rounds but the smith can always check function.
Just my opinion but if I were you I'd send dummy rounds to you smith.
Funny thing I was at the range and bumped into the guy I bought the rifle from. I asked him a bunch of questions he said the chamber was a saami spec with .199 freebore. I asked him how many rounds he had actually fired he stated 40.. I really believe that because I cleaned the gun when I got home with it and it was easily cleaned and patches were really clean and bore felt smooth. From which I have shot it and cleaned it every time I have taken it out. I have right at 290 rounds through it based on my log book and I know it hasn’t gone past 50 rounds without getting cleaned. I really don’t think it’s a carbon issue because I rotate between butches bore shine, sweets, and isso paste and I use bronze brushes every cleaning.. the isso I only use every other or about 100 rounds..
It’s truly baffling that 40.2 grains of H4350 is pegged out on the pressure and the velocity is 2650
4831 with a 140 at 45 grains is barely 2650, and the accuracy node is at 42.5 grains and does 2550.
I loaded RL 17 and found a decent accuracy node around 42.4 grains, it shoots about 3/4 moa and runs 2889 but this is a highly temp sensitive powder and likely won’t play well in the summer time so I never tried to tune it and get below the 3/4 moa it produces.
I asked the gunsmith who built it what his opinion was and he shrugged it off and says well I’m sure the throat is gone because that’s the only reason you can’t make any velocity and said borescoping runs $80, I didn’t pay, and won’t pay that.
needless to say, I’m gonna move on to a better smith. Disappointed for sure.
It’s truly baffling that 40.2 grains of H4350 is pegged out on the pressure and the velocity is 2650
4831 with a 140 at 45 grains is barely 2650, and the accuracy node is at 42.5 grains and does 2550.
I loaded RL 17 and found a decent accuracy node around 42.4 grains, it shoots about 3/4 moa and runs 2889 but this is a highly temp sensitive powder and likely won’t play well in the summer time so I never tried to tune it and get below the 3/4 moa it produces.
I asked the gunsmith who built it what his opinion was and he shrugged it off and says well I’m sure the throat is gone because that’s the only reason you can’t make any velocity and said borescoping runs $80, I didn’t pay, and won’t pay that.
needless to say, I’m gonna move on to a better smith. Disappointed for sure.
Upgrades & Donations
This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.