Ramshot Hunter, 280 Ackley Improved

[AZ82New]

I worked up a load with Hunter and 139 Barnes LRX.

-average 3,275 fps

- .720 MOA for five shots. Three shots at .510.

- SD was 9

This was going to be my go to load.

No pressure, good standard deviation, accurate. Plus, lots of energy out to 600 yards. The bullet, being all copper, should penetrate well. Additionally it's still hitting at around 2,300 fps at 600 yards. The ideal minimum for a Barnes bullet.

What gives me pause is that last week, that load started to fall apart after 25 rounds. Slow three shot groups, with decent breaks but the last several rounds starting showing pressure. Sticky bolt lift and extractor marks.

The ammo was exposed to the sun, so I figured that plus the chamber heating up, pushed the load too far.

So today, I slow things way down and keep the ammo out of the Sun. Still very accurate at 100 yards, but at 425, I'm getting like 8 inch groups. It's all vertical spread. So I throw the chrono on, my SD is 33.

***?

So I'm guessing that Hunter is extremely temp sensitive? Different temp today, hot chamber messes with the powder?

Also, I was shooting into a very minor headwind. Maybe the variation in the headwind could have caused that much variation?

Nonetheless, I just paid wayyyy too much for 5 pounds of IMR 7828 on gunbroker.

Can someone with more experience chime in? Do I ditch this powder? Is there something else I'm doing wrong?

 

[WildRose]

I worked up a load with Hunter and 139 Barnes LRX.

-average 3,275 fps

- .720 MOA for five shots. Three shots at .510.

- SD was 9

This was going to be my go to load.

No pressure, good standard deviation, accurate. Plus, lots of energy out to 600 yards. The bullet, being all copper, should penetrate well. Additionally it's still hitting at around 2,300 fps at 600 yards. The ideal minimum for a Barnes bullet.

What gives me pause is that last week, that load started to fall apart after 25 rounds. Slow three shot groups, with decent breaks but the last several rounds starting showing pressure. Sticky bolt lift and extractor marks.

The ammo was exposed to the sun, so I figured that plus the chamber heating up, pushed the load too far.

So today, I slow things way down and keep the ammo out of the Sun. Still very accurate at 100 yards, but at 425, I'm getting like 8 inch groups. It's all vertical spread. So I throw the chrono on, my SD is 33.

***?

So I'm guessing that Hunter is extremely temp sensitive? Different temp today, hot chamber messes with the powder?

Also, I was shooting into a very minor headwind. Maybe the variation in the headwind could have caused that much variation?

Nonetheless, I just paid wayyyy too much for 5 pounds of IMR 7828 on gunbroker.

Can someone with more experience chime in? Do I ditch this powder? Is there something else I'm doing wrong?

You may also be building up a carbon ring just ahead of the chamber. Might want to give it a serious carbon scrubbing and see if that changes your equation.

Hunter is supposed to be pretty temp stable but you're going to get some variation with any powder with a big shift in temps.

 

[Bret GRAVELINE Graveline]

How many shots are you firing before cleaning, and how well are you scrubing the barrel?

 

[LongWalker]

I ran into a similar issue with a 30-06 running a Berger 180 EH in front of VV N-550. Temp was about 30 degrees warmer than when I developed the load and it basically started shooting like the next charge weight up. As always I checked everything else I could and all of that was fine. I plan to reshoot it this week to confirm that it was indeed temp sensitivity.

I actually ended up taking my 280AI on the hunt which runs RL-23 and had zero issues.

 

[AZ82New]

Prior to each of the two range sessions I cleaned the rifle using a bore snake and #9 solvent. I pass the snake through the bore 3-4 times and use a fairly liberal application of the solvent. The bore always looks shiny and clean to me.

I also periodically use a copper solvent because I'm shooting Barnes.

I suspect that it's with temp sensitivity in the powder or an inconsistency in my reloading process. These are compressed loads, maybe if I tapped the cases so the powder settled evenly in each load?

 

[WildRose]

Prior to each of the two range sessions I cleaned the rifle using a bore snake and #9 solvent. I pass the snake through the bore 3-4 times and use a fairly liberal application of the solvent. The bore always looks shiny and clean to me.

I also periodically use a copper solvent because I'm shooting Barnes.

I suspect that it's with temp sensitivity in the powder or an inconsistency in my reloading process. These are compressed loads, maybe if I tapped the cases so the powder settled evenly in each load?

I'd say then there's a very good chance you've built up a carbon ring then.

If you don't have access to a bore scope or someone with one I'd suggest following one of the various methods specific to removing them.

Len started a thread on it a few years back, I'll look and see if I can find it.


I alternate a bore bush with a patch wrapped around it using first Berryman's Carb cleaner or Boretech Carbon Remover and JB bore paste on a rod. The main area for these buidups is the first three inches of your bore and they can cause catastrophic pressure spikes if they are ignored.

If I can find that thread I'll edit.

EDTA:

Different thread, same problem.

Carbon ring

I've got a relatively new 7 WSM Bartlein barrel on a custom action. The barrel has about 500 rounds on it and has been cleaned regularly. It was never shot hot. The barrel is loosing accuracy fast and nothing seems to help. I took a look through the bore scope and found a jet black carbon ring...

www.longrangehunting.com

 

[Bret GRAVELINE Graveline]

From the sounds of it I suspect a fowling problem, I think you need to be a little more aggressive cleaning the bore, a bore snake is not enough with many barrels, try a saturated bore brush with hoppies about 10 to 12 passes thru the bore and let sit about 15 minutes, patch dry, saturate a patch with aceitone to clean out any residue, patch dry and then treat with Barnes cr10, without a bore scope I'd treat it it 2 or 3 time with the Barnes, then head back to the range, I purchased my bore scope over 30 years ago, it was a real eye opener, back then most shooters just cleaned with a little hoppies and called it good, discovered most barrels we thought to be cleaned really weren't, I'd say 3 out out of 5 rifles brought into my shop back then with accuracy issues just really needed a good cleaning, today's barrels are of better quality than they were back then, but once a build up occurs weather carbon or copper it can create all kinds of issues, be it pressures or accuracy.

 

[AZ82New]

Thank you all for the replies, I'll be cleaning the out of the barrel and we'll see how it performs.

 

[WYO300RUM]

How many shots are you firing before cleaning, and how well are you scrubing the barrel?

Awesome blacktail in your avitar. Don't want to change subject but did you score it ?
Sorry everyone !

 

[skipglo]

I haven't seen anyone ask....how many grains are you loading of powder that is? It never hurts to do a thorough cleaning but maybe a grain or two either way may make the difference! Just me.

 

[Bret GRAVELINE Graveline]

Awesome blacktail in your avitar. Don't want to change subject but did you score it ?
Sorry everyone !

Yes but I really don't remember, I scored it SCI, its basically the same as B&C without deductions, I think it was 162 or 67, I'd go score it but its at the taxidermist, technically its is not considered a true blacktail, location was about 25 miles to far east to be considered a blacktail, been hunting these critters for 52 years, and mule deer in most of the western states for about 45, once in awhile we run into a mule deer on our side of the mountain, you know when you're looking at a mule deer, but rules are rules

 

[xsn10s]

So I'm guessing that Hunter is extremely temp sensitive? Different temp today, hot chamber messes with the powder?

One temp sensitivety chart I saw claims .86 fps per every degree so not temp stable. But it isn't really that bad either. AZ can have some pretty bad temp swings so I cannot rule that out. It could be carbon ring, could be a badly copper fouled barrel. Also if you're shooting a compressed load with a ball powder then you may want to try a magnum primer. You'd have to restart the load workup since the mag primer can raise pressures.

 

[WYO300RUM]

Yes but I really don't remember, I scored it SCI, its basically the same as B&C without deductions, I think it was 162 or 67, I'd go score it but its at the taxidermist, technically its is not considered a true blacktail, location was about 25 miles to far east to be considered a blacktail, been hunting these critters for 52 years, and mule deer in most of the western states for about 45, once in awhile we run into a mule deer on our side of the mountain, you know when you're looking at a mule deer, but rules are rules

You can tell by the black on the tail. 5 different types muledeer not counting blacktail. Burro deer down south/ desert get some big racks. Inyo and Rocky mtn. species in Sierras get big but east side they migtlrate back and forth from Nevada. I burned my points last year and drew X12 . Hunted out of Bridgeport and in Bodie state park. X12 my favorite hunt there. Shot a nice 4x4 e/eyegaurds . I've only shot one blacktail in Ca.. Was out of Weaverville. The hybrid muley/blacktail are getting common in L.A. county. I lived in San Bernardino and San Diego counties for most my life. Hunted Wy. for 37 years before moving . Glad I'm out of Ca.. Beautiful state that has everything. One party ruined it... Look at the pictures of the different tails on F&G website. I'm not calling it Jerry Brown's new name. I still have max pts. for elk there. Non res tag is over $1500.00 ! What a joke. Other states half that. Awesome BLACKTAIL buck anyway !
Oh yeah , back to topic ! Sorry!!!

 

[xsn10s]

I've only shot one blacktail in Ca.. Was out of Weaverville. The hybrid muley/blacktail are getting common in L.A. county. I lived in San Bernardino and San Diego counties for most my life. Hunted Wy. for 37 years before moving . Glad I'm out of Ca.. Beautiful state that has everything.

It used to be a sportman's paradise and a bit of a firearm's mecca. It's truely a shame what happened. Oh well on to new happy hunting/ fishing adventures!