Grendel in the Cold

[eleaf]

I was out shooting my new 6.5 Grendel in the cold today, and I've got a few questions.

First some facts:
Brand new gun - never shot before today
I never lubed it. The only lube it had was whatever AA applied before shipping me the rifle.
Temp: floating between 30 and 32 with a very modest breeze.


I went to zero the gun. All was well. She fired everything except a couple hand loads that were sketchy to begin with (took me a while to find the sweet spot with the resizing die), including other hand loads that worked great. No problems there. Everything went bang, everything cycled with no issues. Rounds fed from the mag without issue, and they all ejected in to my awaiting rifle case that was strategically left open to my right in order to catch all of this really expensive Grendel brass. Finally found my zero and we were on our way.

We put the rifles in the heated truck and go from where we zeroed to the long range, got out of car and went to shooting platform.

Everything went bang (and I was slammin' targets out to 700 - my first time out further than 300 so forgive my giddiness about the deal) but I couldn't get jack to cycle correctly. Every round ejected, but not a single round fed from the magazine after a shot had been fired. Essentially, I was reduced to shooting single shot, and even then the bolt wouldn't stay locked to the rear (it always closed no matter the situation).

After some google-fu, I *THINK* I was dealing with freezing condensation issues. Sub-freezing temps (for an hour or more) to warm vehicle inside a cozy case, back to sub-freezing in a short span with no acclimation period.

I also, because my bolt wouldn't lock back with an empty magazine, *THINK* that the likely culprit was the magazines freezing up (all of which functioned perfectly while I was zeroing the weapon). I just can't think of anything else that it could be.

The gun seemed to function fine except that it would not feed from the magazine after a shot was taken. It would load one in to the chamber when I manually cycled it with the charging handle, but never as intended.

If anyone can help, or even just confirm my suspicions, I'd greatly appreciate it.

Anything I might do (lube, oil, what have you) which might mitigate the issue (other than simply allowing the rifle to properly acclimate and get rid of condensation before bringing it back out in the cold) would be gravy.

Thanks.

 

[LoneWolfUSMC]

Re: Grendel in the Cold

I don't think you were having much of a freeze-up issue at 30-32*F. The first couple of shots would have warmed the weapon up. If it was freezing up I could see it causing problems from the first couple of shots, then running well.

I think what you may have seen is a tight new rifle, that you burned the modest factory lube out of, then ran dry.

In normal winter temps I have not had any issues with Miltec1 as a lube. When you get into sub-zero temps then you need lubes specifically designed to operate in those environments.

The general rule of thumb is when an AR has issues, break it down and lube it first.

 

[Killshot44]

Re: Grendel in the Cold

ARs love lube almost as much as Mormon women. You can get some $17 per 1/2 Oz stuff or just use Mobile 1 5w30. Lube the BCG skids and behind the bolt lugs. Shame on you for running her dry the first time out. I'da bit you.

Enough lube = no more sticky...

32º ain't even <span style="font-style: italic">starting</span> to be "cold"........

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LoneWolfUSMC</div><div class="ubbcode-body">I don't think you were having much of a freeze-up issue at 30-32*F. The first couple of shots would have warmed the weapon up. If it was freezing up I could see it causing problems from the first couple of shots, then running well.

I think what you may have seen is a tight new rifle, that you burned the modest factory lube out of, then ran dry.

In normal winter temps I have not had any issues with Miltec1 as a lube. When you get into sub-zero temps then you need lubes specifically designed to operate in those environments.

The general rule of thumb is when an AR has issues, break it down and lube it first. </div></div>

I agree that it seems weird to see freezing issues with "mild" temps, but how does a lack of lube explain the fact that it worked like butter at one spot, then just 10 minutes later at a different spot, problems arose (all after seeing temp shifts)?

There's just too much coincidence to just blame it on lube, no?

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Killshot44</div><div class="ubbcode-body">ARs love lube almost as much as Mormon women. You can get some $17 per 1/2 Oz stuff or just use Mobile 1 5w30. Lube the BCG skids and behind the bolt lugs. Shame on you for running her dry the first time out. I'da bit you.

Enough lube = no more sticky...

32º ain't even <span style="font-style: italic">starting</span> to be "cold"........ </div></div>

I don't think that the 32 was freezing up the gun (meaning I don't think that the "cold" was the culprit or that it itself was seizing any of the parts), but the fluctuations in temperature.

32 degrees freezes small droplets of condensation just as frozen as real cold.

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Killshot44</div><div class="ubbcode-body">ARs love lube almost as much as Mormon women. You can get some $17 per 1/2 Oz stuff or just use Mobile 1 5w30. Lube the BCG skids and behind the bolt lugs. Shame on you for running her dry the first time out. I'da bit you.

Enough lube = no more sticky...

32º ain't even <span style="font-style: italic">starting</span> to be "cold"........ </div></div>

I just opened her up for a quick inspection/cleaning/lube job and I'm even more critical of the "it just needs lube" theory. Not only was there still lube from the factory, but plenty of it. A nice sheen gloss of oil/lube mixed with a bit of dirty covering everything of import: the BC, bolt, firing pin, and and along the walls of the upper. Not drippy wet, but definitely far from dry.

I've lubed her up with some CLP for now and will bring her out in the next few days to see if she's alive again or whether she needs further lookin'.

 

[bigwheeler]

Re: Grendel in the Cold

Can't say what it was, but it doesn't sound like a magazine problem. The carrier
sounds like it was short stroking. Water in the buffer tube freezing up is where
I would be looking. The exhaust hole at the rear may have frozen shut from moisture that you could have induced by warming up the gun in the truck. With
the air flow it causes a chill factor that lowers the effective temp on water a lot.
Maybe I'm all wet (or all ice) with this but it's my guess.

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bigwheeler</div><div class="ubbcode-body"> Can't say what it was, but it doesn't sound like a magazine problem. The carrier
sounds like it was short stroking. Water in the buffer tube freezing up is where
I would be looking. The exhaust hole at the rear may have frozen shut from moisture that you could have induced by warming up the gun in the truck. With
the air flow it causes a chill factor that lowers the effective temp on water a lot.
Maybe I'm all wet (or all ice) with this but it's my guess. </div></div>

Many thanks. But I have a question.

Wouldn't a couple of shots dealt with a small ice particle problem there? I mean, there is hot gas going through that tube which should have melted any ice that might have been there.
I probably took 20 or 25 shots in single shot mode with no improvement in feeding. The gun shot fine (and I mean when reducing the action for shooting a semi auto in to different parts, it went bang and a round went down range while the brass was ejected). It seems that if there might have been any ice crystals in the gas tube, 25 shots should have been enough to eviscerate those 10 times over.

But in the event that short stroking is the issue (even if not caused by ice obstruction in the gas tube), I put in a new buffer and spring. At the very least it can't hurt.

 

[Redmanss]

Re: Grendel in the Cold

If I'm reading everything right... 30-32*F, sufficient lube in all the metal-metal contact areas, no signs of abnormal parts wear or broken parts, short stroke is the only symptom...

Ice crystals begin forming at ~32-34*F (depending on altitude/pressure), and your rifle's metal temperature would have to hit that low to start the crystals forming, not just the air temperature. Bringing the rifle out of a heated truck into the cold, while you will see condensation issues depending on your humidity at the time, shouldn't be significant enough to actually ice it up. If you didn't physically see any ice, it probably wasn't there.

I would look at your loads, especially since you were having issues with them during zeroing. You may have them undercharged or charged with a power that is more susceptible to the cold. Basically, it sounds like you're underpowered for the cold and that is what is causing it to short stroke. If you have or can find any, try some factory loads for comparison.

Throw the question out in the reloading forum and see what hits you get.

 

[Redmanss]

Re: Grendel in the Cold

Also, did you check to make sure your gas key didn't come loose? It may have vibrated loose with your shooting, and that's why it worked fine before and now it isn't. Just another possibility...

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Redmanss</div><div class="ubbcode-body">If I'm reading everything right... 30-32*F, sufficient lube in all the metal-metal contact areas, no signs of abnormal parts wear or broken parts, short stroke is the only symptom...

Ice crystals begin forming at ~32-34*F (depending on altitude/pressure), and your rifle's metal temperature would have to hit that low to start the crystals forming, not just the air temperature. Bringing the rifle out of a heated truck into the cold, while you will see condensation issues depending on your humidity at the time, shouldn't be significant enough to actually ice it up. If you didn't physically see any ice, it probably wasn't there.

I would look at your loads, especially since you were having issues with them during zeroing. You may have them undercharged or charged with a power that is more susceptible to the cold. Basically, it sounds like you're underpowered for the cold and that is what is causing it to short stroke. If you have or can find any, try some factory loads for comparison.

Throw the question out in the reloading forum and see what hits you get. </div></div>

I think this is actually my problem.

I misread Alexander Arms' reload data. They recommend a CCI 450 primer, which I interpreted as a Small Rifle Bench Rest Primer, rather than the correct Small Rifle Magnum Primer (normally I consider myself dumb, not stupid, but there are times when both apply).

Loads are good. I'm just under the max.

Factory ammo shot like butter.

I've also been reading on barfcom that ball propellants (and especially in 6.5 Grendel) really like to be used with magnum primers, especially in colder weather, and that one of the things one is likely to see will be . . . short stroking.

Will hit Sportsmans Warehouse tomorrow in hopes they have some SR Magnum primers in stock and go from there.

Thanks for the help.

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Redmanss</div><div class="ubbcode-body">Also, did you check to make sure your gas key didn't come loose? It may have vibrated loose with your shooting, and that's why it worked fine before and now it isn't. Just another possibility... </div></div>

Gas key is good. Think it's the loads and lack of magnum primer with this particular propellant (A 2520).

 

[Redmanss]

Re: Grendel in the Cold

You're welcome. Glad it isn't the rifle and is just a cheap fix instead.

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Redmanss</div><div class="ubbcode-body">You're welcome. Glad it isn't the rifle and is just a cheap fix instead. </div></div>

I'll be a bit more cautious and give it a TBD right now.

I won't call it fixed until I have some rounds loaded and tested without issue.

That said, I was slammin' some steel at 700 yards today (first time at anything beyond 300 yards). It was a bit frustrating though because of the short stroking, though no less gratifying. If I wanted a single shot, I'd have bought one!!

Again, many thanks.

 

[bigwheeler]

Re: Grendel in the Cold

The buffer tube, not the gas tube.


<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: eleaf</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bigwheeler</div><div class="ubbcode-body"> Can't say what it was, but it doesn't sound like a magazine problem. The carrier
sounds like it was short stroking. Water in the buffer tube freezing up is where
I would be looking. The exhaust hole at the rear may have frozen shut from moisture that you could have induced by warming up the gun in the truck. With
the air flow it causes a chill factor that lowers the effective temp on water a lot.
Maybe I'm all wet (or all ice) with this but it's my guess. </div></div>

Many thanks. But I have a question.

Wouldn't a couple of shots dealt with a small ice particle problem there? I mean, there is hot gas going through that tube which should have melted any ice that might have been there.
I probably took 20 or 25 shots in single shot mode with no improvement in feeding. The gun shot fine (and I mean when reducing the action for shooting a semi auto in to different parts, it went bang and a round went down range while the brass was ejected). It seems that if there might have been any ice crystals in the gas tube, 25 shots should have been enough to eviscerate those 10 times over.

But in the event that short stroking is the issue (even if not caused by ice obstruction in the gas tube), I put in a new buffer and spring. At the very least it can't hurt. </div></div>

 

[ranger1183]

Re: Grendel in the Cold

what you just described happened to me one time. I thought, as well as everyone else, that the rifle was short stroking. It turned out to be the exact opposite.

There was so much gas going through the system that the rifle didn't have enough time to complete the extraction/ejection process before it tried to feed the next round. I had to slow down the cycling process by either limiting how much gas went through the system or by using one of those hydraulic pistons that replace the buffer tube.

I got my gunsmith to put a metering plug in the gas system that I turned down until everything worked at the proper speed. She has run like a champ ever since.

good luck!

 

[jbailey]

Re: Grendel in the Cold

So all the single-cycling was on hand-loaded ammo? Did you fire any factory ammo?

On the hand-loads, I would never use a benchrest primer in cold weather, especially CCI. They just don't produce enough ignition power.

Also, what kind of wind were you dealing with? Just curious to hear more about the range report / 700yd shooting. Wind is the biggest factor when moving from 300 to 700...

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bigwheeler</div><div class="ubbcode-body">The buffer tube, not the gas tube.</div></div>

That's what I get for responding late at night.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: eleaf</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bigwheeler</div><div class="ubbcode-body"> Can't say what it was, but it doesn't sound like a magazine problem. The carrier
sounds like it was short stroking. Water in the buffer tube freezing up is where
I would be looking. The exhaust hole at the rear may have frozen shut from moisture that you could have induced by warming up the gun in the truck. With
the air flow it causes a chill factor that lowers the effective temp on water a lot.
Maybe I'm all wet (or all ice) with this but it's my guess. </div></div>

Many thanks. But I have a question.

Wouldn't a couple of shots dealt with a small ice particle problem there? I mean, there is hot gas going through that tube which should have melted any ice that might have been there.
I probably took 20 or 25 shots in single shot mode with no improvement in feeding. The gun shot fine (and I mean when reducing the action for shooting a semi auto in to different parts, it went bang and a round went down range while the brass was ejected). It seems that if there might have been any ice crystals in the gas tube, 25 shots should have been enough to eviscerate those 10 times over.

But in the event that short stroking is the issue (even if not caused by ice obstruction in the gas tube), I put in a new buffer and spring. At the very least it can't hurt. </div></div> [/quote]

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JamesBailey</div><div class="ubbcode-body">So all the single-cycling was on hand-loaded ammo? Did you fire any factory ammo?</div></div>

I shot 2 full boxes of AA Lapua 123 Factory ammo, and it shot like butter. No problems. But it was before we got back in the truck and reintroduced to cold weather.

But to answer your question, yes I shot factory ammo and it worked great. Being that AA recommends magnum primers for ALL of the loads in their published data (regardless of powder or bullet), I'm going to assume that they use them in their factory ammo.

I haven't used magnum primers before, but I will say that the primers in factory loads were silver whereas mine are gold (I was using Rem 7 1/2 BR primers).

Don't really know if color is indicative of the type of primer being used (I don't think so, but really have no idea).

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">On the hand-loads, I would never use a benchrest primer in cold weather, especially CCI. They just don't produce enough ignition power.</div></div>

Good to know. Thanks. Would that be for all loads and calibers, or just the 6.5 Grendel?

I've used standard CCI LR primers in really cold (<20 degrees) in my .308 and never had any issues.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Also, what kind of wind were you dealing with? Just curious to hear more about the range report / 700yd shooting. Wind is the biggest factor when moving from 300 to 700...
</div></div>

It was a modest breeze, though steady (don't have a real reading, though it was enough to make fairly cold to damn cold on the raised platform we were shooting from). I didn't have to do any more than aim just off the right edge of the 25% IPSC target which would create hits anywhere from center to left edge. Wind was right to left coming in from 2 o'clock or perhaps 2:30. It was mostly a cross-wind, but it was definitely coming in at diagonally as well.

When I moved on to the smaller targets at 700, I never hit them, but I was dancing around them real close according to my spotter. I only took 2 or 3 shots before we gave up from the cold (we had already been out for ~3 hours by then). Plus my short stroking issues were making shooting increasingly frustrating (I gave up and resorted to single shot with every round).


I've picked up some CCI 450 SR Magnum primers today (2000 of them), and will be trying them in the next couple of days with the same powder/bullet/brass combo to see if this fixes my issues.

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ranger1183</div><div class="ubbcode-body">what you just described happened to me one time. I thought, as well as everyone else, that the rifle was short stroking. It turned out to be the exact opposite.

There was so much gas going through the system that the rifle didn't have enough time to complete the extraction/ejection process before it tried to feed the next round. I had to slow down the cycling process by either limiting how much gas went through the system or by using one of those hydraulic pistons that replace the buffer tube.

I got my gunsmith to put a metering plug in the gas system that I turned down until everything worked at the proper speed. She has run like a champ ever since.

good luck! </div></div>

I don't think that is my problem. Extraction and ejection are not the problem. It's feeding. The bullet isn't even touched in the magazine. It appears as if the gun didn't even try to feed anything.

 

[BOLTRIPPER]

Re: Grendel in the Cold

my advice.......try FRESH ROasted fresh brewed coffee

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BOLTRIPPER</div><div class="ubbcode-body">my advice.......try FRESH ROasted fresh brewed coffee </div></div>

I HATE coffee. Always have.

But a nice thermos of hot cocoa or tea would probably do the trick.

 

[Flynn]

Re: Grendel in the Cold

sounds as though it's short stroking.

Underpowered ammo?
Oversprung?
buffer too heavy?

 

[KYS]

Re: Grendel in the Cold

Im just glad we got to get out there and ring some steel! Even though it was freezing and I didnt wear my base layer.

 

[jbailey]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: eleaf</div><div class="ubbcode-body">

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">On the hand-loads, I would never use a benchrest primer in cold weather, especially CCI. They just don't produce enough ignition power.</div></div>

Good to know. Thanks. Would that be for all loads and calibers, or just the 6.5 Grendel?

I've used standard CCI LR primers in really cold (<20 degrees) in my .308 and never had any issues.
</div></div>

Benchrest primers suck in cold weather for all calibers. With a bolt gun, you will not notice it as much unless you have a chrono or are observing way too much bullet drop (due to the lower MV). With a semi-auto, they can result in crappy cycling, as you probably found out.


<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">
It was a modest breeze, though steady (don't have a real reading, though it was enough to make fairly cold to damn cold on the raised platform we were shooting from). I didn't have to do any more than aim just off the right edge of the 25% IPSC target which would create hits anywhere from center to left edge. Wind was right to left coming in from 2 o'clock or perhaps 2:30. It was mostly a cross-wind, but it was definitely coming in at diagonally as well.

When I moved on to the smaller targets at 700, I never hit them, but I was dancing around them real close according to my spotter. I only took 2 or 3 shots before we gave up from the cold (we had already been out for ~3 hours by then). Plus my short stroking issues were making shooting increasingly frustrating (I gave up and resorted to single shot with every round).
</div></div>

You were shooting in a 2 to 4 mph wind.

At least per my math:
25% IPSC target = 11.25" (1.6moa at 700yds). Holding off right edge means you were holding 6-8" off the center and if your bullets were hitting center to left edge, that means they were deflecting 8-12". A 123gr AMax doing 2500 MV in 0.08 lb/ft^3 air density (I assumed both of those conditions) deflects approximate 4-5" at 700yds in 1 mph of wind, which means it requires 2 to 3mph wind to move it 8-12". You said the wind was at 2 oclock so its a .9 value wind, meaning it might require 4mph to move bullet all the way to left edge.

As a compare, 77gr SMK would deflect 15" to 28" in those same conditions, meaning the 6.5" has around 50% less wind deflection at that range.

Consistent hits on a 1.6moa target is impressive - good shooting!

 

[DHDeal]

Re: Grendel in the Cold

Even though the Remington 7 1/2 maybe listed as a benchrest primer, it is as strong as the CCI450. German Salazar did a good article on SR primers a while back and the 7 1/2 was definately not a weakling. If I remember correctly, he said it was too strong for his purposes, and again I believe, that was testing the Lapua 308 Palma brass.

The 6.5 Grendel I have, has done well with 205, 205M, Rem 7 1/2, and lastly the CCI 450 primers. The sd's were lowest with the CCI 450's fwiw (and I mean low sd's too). If only the groups were as good as the data, Damnit!

 

[Arboreal]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Killshot44</div><div class="ubbcode-body">ARs love lube almost as much as Mormon women.</div></div>

You got a lot of experience with Mormon women?

 

[KYS]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JamesBailey</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: eleaf</div><div class="ubbcode-body">

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">On the hand-loads, I would never use a benchrest primer in cold weather, especially CCI. They just don't produce enough ignition power.</div></div>

Good to know. Thanks. Would that be for all loads and calibers, or just the 6.5 Grendel?

I've used standard CCI LR primers in really cold (<20 degrees) in my .308 and never had any issues.
</div></div>

Benchrest primers suck in cold weather for all calibers. With a bolt gun, you will not notice it as much unless you have a chrono or are observing way too much bullet drop (due to the lower MV). With a semi-auto, they can result in crappy cycling, as you probably found out.


<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">
It was a modest breeze, though steady (don't have a real reading, though it was enough to make fairly cold to damn cold on the raised platform we were shooting from). I didn't have to do any more than aim just off the right edge of the 25% IPSC target which would create hits anywhere from center to left edge. Wind was right to left coming in from 2 o'clock or perhaps 2:30. It was mostly a cross-wind, but it was definitely coming in at diagonally as well.

When I moved on to the smaller targets at 700, I never hit them, but I was dancing around them real close according to my spotter. I only took 2 or 3 shots before we gave up from the cold (we had already been out for ~3 hours by then). Plus my short stroking issues were making shooting increasingly frustrating (I gave up and resorted to single shot with every round).
</div></div>

You were shooting in a 2 to 4 mph wind.

At least per my math:
25% IPSC target = 11.25" (1.6moa at 700yds). Holding off right edge means you were holding 6-8" off the center and if your bullets were hitting center to left edge, that means they were deflecting 8-12". A 123gr AMax doing 2500 MV in 0.08 lb/ft^3 air density (I assumed both of those conditions) deflects approximate 4-5" at 700yds in 1 mph of wind, which means it requires 2 to 3mph wind to move it 8-12". You said the wind was at 2 oclock so its a .9 value wind, meaning it might require 4mph to move bullet all the way to left edge.

As a compare, 77gr SMK would deflect 15" to 28" in those same conditions, meaning the 6.5" has around 50% less wind deflection at that range.

Consistent hits on a 1.6moa target is impressive - good shooting!



</div></div>

I think he got a little confused. They were not 25% IPSC targets we were shooting at. The 600 yard target is a 18x12 silhouette that was cut out by hand and its not official size. The 700 yard target that he was hitting was a 45% IPSC target that was made by OSU. Still great shooting for a range he had never shot at or attempted that kind of distance.

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KYS338</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JamesBailey</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: eleaf</div><div class="ubbcode-body">

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">On the hand-loads, I would never use a benchrest primer in cold weather, especially CCI. They just don't produce enough ignition power.</div></div>

Good to know. Thanks. Would that be for all loads and calibers, or just the 6.5 Grendel?

I've used standard CCI LR primers in really cold (<20 degrees) in my .308 and never had any issues.
</div></div>

Benchrest primers suck in cold weather for all calibers. With a bolt gun, you will not notice it as much unless you have a chrono or are observing way too much bullet drop (due to the lower MV). With a semi-auto, they can result in crappy cycling, as you probably found out.


<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">
It was a modest breeze, though steady (don't have a real reading, though it was enough to make fairly cold to damn cold on the raised platform we were shooting from). I didn't have to do any more than aim just off the right edge of the 25% IPSC target which would create hits anywhere from center to left edge. Wind was right to left coming in from 2 o'clock or perhaps 2:30. It was mostly a cross-wind, but it was definitely coming in at diagonally as well.

When I moved on to the smaller targets at 700, I never hit them, but I was dancing around them real close according to my spotter. I only took 2 or 3 shots before we gave up from the cold (we had already been out for ~3 hours by then). Plus my short stroking issues were making shooting increasingly frustrating (I gave up and resorted to single shot with every round).
</div></div>

You were shooting in a 2 to 4 mph wind.

At least per my math:
25% IPSC target = 11.25" (1.6moa at 700yds). Holding off right edge means you were holding 6-8" off the center and if your bullets were hitting center to left edge, that means they were deflecting 8-12". A 123gr AMax doing 2500 MV in 0.08 lb/ft^3 air density (I assumed both of those conditions) deflects approximate 4-5" at 700yds in 1 mph of wind, which means it requires 2 to 3mph wind to move it 8-12". You said the wind was at 2 oclock so its a .9 value wind, meaning it might require 4mph to move bullet all the way to left edge.

As a compare, 77gr SMK would deflect 15" to 28" in those same conditions, meaning the 6.5" has around 50% less wind deflection at that range.

Consistent hits on a 1.6moa target is impressive - good shooting!



</div></div>

I think he got a little confused. They were not 25% IPSC targets we were shooting at. The 600 yard target is a 18x12 silhouette that was cut out by hand and its not official size. The 700 yard target that he was hitting was a 45% IPSC target that was made by OSU. Still great shooting for a range he had never shot at or attempted that kind of distance. </div></div>

Thanks for the correction.

I only remember you once mentioning IPSC silhouettes, and I thought I remembered 25%. Which one was the tall skinny I was shooting at?

Oh well.

The 600 yards is twice the distance I've ever shot at. 700 yards is 2.3x. Thought I did okay. Was pleased as punch regardless.

 

[KYS]

Re: Grendel in the Cold

You did great. Minus my hands going numb I had a decent day. Probably should have remembered more ammo but oh well!

The 600 yard "man" is 18"x12". He was just something that a friend in school made. Its Ar500 plate they had left over from making a large grill/smoker.

The 25% targets are reactive one on a tall post at 450 yards and the others spread out around the 500 to 600 yard berm.

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Flynn</div><div class="ubbcode-body">sounds as though it's short stroking.

Underpowered ammo?
Oversprung?
buffer too heavy?
</div></div>

I'm going to go with the ammo spewing it's load too quickly causing a short stroke. I was almost at max load so it shouldn't be an underpowered load (I'm talking specifically about the charge).

The magnum primers should help as it has a stronger, slower burn.

I hope.

The spring is the standard rifle spring and the buffer a standard rifle buffer (both DPMS), so I doubt that's the problem.

That and the factory ammo shot great. Not a single short stroke.

It was my hand loads that were the issue. My only alternative (if it is my loads) is to use the magnum primers (being that is what is in AA's factory ammo and what they have listed in their published data for all of their loads) at this point (of course I could experiment using different powders as well, or toning down the load - which I plan on anyways to do some real load development). If it isn't the primer, it's the gun.

Hopefully it was the primers. That's an easy fix. I already bought the requisite primers and have loaded 20 to take to the range tomorrow for some testing. The load has the same everything but primers.

The gun has been cleaned and lubed (except for the barrel to keep the fouling - I only put about ~60 rounds down the tube) and she's ready to roll.

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KYS338</div><div class="ubbcode-body">You did great. Minus my hands going numb I had a decent day. Probably should have remembered more ammo but oh well!

The 600 yard "man" is 18"x12". He was just something that a friend in school made. Its Ar500 plate they had left over from making a large grill/smoker.

The 25% targets are reactive one on a tall post at 450 yards and the others spread out around the 500 to 600 yard berm. </div></div>

One thing I will say is that the IOR 3.5-18x50 glass I used was AWESOME (especially once I got the parallax adjusted). The MP-8 reticle is the best I've ever used (though admittedly I don't have THAT much experience with high end optics). It puts the NF MLR to shame IMO. A standard mildot doesn't even belong in the same conversation.

 

[jbailey]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KYS338</div><div class="ubbcode-body">
I think he got a little confused. They were not 25% IPSC targets we were shooting at. The 600 yard target is a 18x12 silhouette that was cut out by hand and its not official size. The 700 yard target that he was hitting was a 45% IPSC target that was made by OSU. Still great shooting for a range he had never shot at or attempted that kind of distance. </div></div>

Ok, if the target was a 45% IPSC target, it is 20". Recalculating we get:

You were shooting in a 4 to 7 mph wind.

At least per my math:
45% IPSC target = 20.25" (2.9moa at 700yds). Holding off right edge means you were holding 12-14" off the center and if your bullets were hitting center to left edge, that means they were deflecting 14-24". A 123gr AMax doing 2500 MV in 0.08 lb/ft^3 air density (I assumed both of those conditions) deflects approximate 4-5" at 700yds in 1 mph of wind, which means it requires 4 to 6 mph wind to move it 12-14". You said the wind was at 2 oclock so its a .9 value wind, meaning it might require 7mph to move bullet all the way to left edge.

 

[eleaf]

Re: Grendel in the Cold

Took the Grendel and new rounds with the magnum primers to the range today and they shot like butter.

I really didn't care to shoot for accuracy today so I have no idea how well it shot, but I do know that everything functioned the way it should.

Everything fed. Everything ejected in to my open gun case on the floor beside me.

Now begins the load development to find my optimum load (currently it is running at max per AA's published load data, with no signs of over pressure). I'll do the OCW method to figure out my optimum charge and be on my way.

Thanks for the ideas and help to figure this problem out. Being a relative AR newbie, I NEVER would have guessed that it could be the primers (of all things).

 

[Unknown]

Re: Grendel in the Cold

Ever since I switched to the CCI450 (magnum small rifle) primers, and run both my Grendels really wet with lube, they work great. I make sure brass is trimmed before every loading, and that the brass shoulder is pushed back about 2 thou from the length on rifle with the short chamber. There is a slight difference in chamber length, but not enough to worry about headspace..so I size to the shorter chamber.

With properly sized cases, plenty of lube, mag primers, and enough powder, both rifles run like beautifully.

I quit counting how many loads I get out of a case. I lost track somewhere between 5-7 loadings. When primers get loose, or necks crack (I anneal too) I toss 'em in the recycling brass bucket.

 

[Redmanss]

Re: Grendel in the Cold

Good to know and glad she's running well.

 

[jbailey]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: eleaf</div><div class="ubbcode-body">Now begins the load development to find my optimum load (currently it is running at max per AA's published load data, with no signs of over pressure). I'll do the OCW method to figure out my optimum charge and be on my way.

</div></div>

Eleaf-
This piece was written by a friend of mine on OCW and you might find some use from it:

http://www.shell-central.com/Powder1.html

Ed knows his stuff. I'm shooting against him and that 0.19moa load in a sniper team match at Mayberry GPA (Maryland) in late February.

 

[chase102798]

Re: Grendel in the Cold

eleaf,

My brother in law and I had a similar problem with an AA 6.5 grendel barrel. It was shortly after we put it together (but not the first time it was shot) and we were shooting in PA at prolly temps under 30 degrees. It was January last year. His house is about 80 degrees I swear with his cranked up wood burner. Anyway, we had the gun in the house then out in the cold for a while then in and out. Anyway, at first everything was fine, but then the loaded rounds started sticking in the chamber. When you went to eject a loaded round, the bullet was jammed. At one point, the case pulled loose of the bullet and spilled some powder. We messed with it some more and stuck one or two more. I checked everything. Ammo, lube, dirty?, borescoped the barrel and couldn't see anything obvious. I thought maybe a bad chamber so all I had to sort of check it was go/no-go guages, but the gun had shot and functioned fine on other occasions. Couple weeks later, same deal. Cold outside, hot inside gun in and out a couple times. So he just left it in his cool breezeway when we were shooting in the cold and never had a problem again. Gun has about 300 rounds now and all through the summer, fall, and this winter nothing since.

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: chase102798</div><div class="ubbcode-body">eleaf,

My brother in law and I had a similar problem with an AA 6.5 grendel barrel. It was shortly after we put it together (but not the first time it was shot) and we were shooting in PA at prolly temps under 30 degrees. It was January last year. His house is about 80 degrees I swear with his cranked up wood burner. Anyway, we had the gun in the house then out in the cold for a while then in and out. Anyway, at first everything was fine, but then the loaded rounds started sticking in the chamber. When you went to eject a loaded round, the bullet was jammed. At one point, the case pulled loose of the bullet and spilled some powder. We messed with it some more and stuck one or two more. I checked everything. Ammo, lube, dirty?, borescoped the barrel and couldn't see anything obvious. I thought maybe a bad chamber so all I had to sort of check it was go/no-go guages, but the gun had shot and functioned fine on other occasions. Couple weeks later, same deal. Cold outside, hot inside gun in and out a couple times. So he just left it in his cool breezeway when we were shooting in the cold and never had a problem again. Gun has about 300 rounds now and all through the summer, fall, and this winter nothing since. </div></div>

It turns out that the cold/warm/cold wasn't my problem, but the fact that I was using bench rest primers rather than magnum primers.

That said, the best way to deal with freezing condensation is to always allow the rifle to acclimate before changing temperatures.

If you're shooting in the cold, leave the rifle outside if you plan on continuing to shoot. If you do bring it inside, allow it to completely acclimate to the warm and allow any condensation to completely evaporate before bringing it back out.

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JamesBailey</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: eleaf</div><div class="ubbcode-body">Now begins the load development to find my optimum load (currently it is running at max per AA's published load data, with no signs of over pressure). I'll do the OCW method to figure out my optimum charge and be on my way.

</div></div>

Eleaf-
This piece was written by a friend of mine on OCW and you might find some use from it:

http://www.shell-central.com/Powder1.html

Ed knows his stuff. I'm shooting against him and that 0.19moa load in a sniper team match at Mayberry GPA (Maryland) in late February.

</div></div>

Thanks for the link. Good stuff.

 

[rangertmldr]

Re: Grendel in the Cold

Sounds like you got it figured out, but check to make sure you bumped your shoulder back wnough when sizing the brass.

 

[eleaf]

Re: Grendel in the Cold

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rangertmldr</div><div class="ubbcode-body">Sounds like you got it figured out, but check to make sure you bumped your shoulder back wnough when sizing the brass. </div></div>

That was an early problem that has since been solved before I shot a single round. The Sheridan Function Test Gauge is money in the bank. Take a loaded (or dummy round), slip it in, if it fits it'll work, if not it won't. Every finished round goes in this gauge before being put in the ammo box.

I also went ahead and ordered the LE Wilson headspace gauge so I can test the brass before I prime, charge, and seat and catch any potential problems before I finish the bullet only to have to pull it and start over.