Allen Mag Shooters Group

[41mag]

Well I have been thinking about this for a while and figure rather than spread all of our findings out in various threads why not just keep it all in one. So I decided to fire away and start it off. IF you thinki it might help out with the folks who are just getting into them feel free to pass along any input you feel pertentant, or ask questions about things your looking to try. Like was mantioned, it might help someone save some barrel wear or components.

This rigs are made for two things, reaching out and touching something with authority, and burning large amounts of powder doing so.

So here we go,

Roy, As Tim mentioned in the other post, down here it is very hard to get some of the load densities that others are getting. Even using the 872 we are still somewhere between 4-6 or so grains behind most in our loads. Using 869 I have loaded up to 102grs, however this was only when the temps were hovering around the low 70's. Even at the upper 70's tepms a 100gr load was showing some pretty significant extractor marks.

Stephen,

I don't have any 150 NBT's at this time but here is a Solid Base in with the 169.5 & 195 Wildcat's for comparison,

From left to right, 150gr Nosler Solid Base, 169.5 Wildcat, 195gr Wildcat

Hope this helps, I just figured that we could use one thread to summarize our data rather than spreading it out between several. It doesn't have to be exclusively for the .270 or .277, but it will make searching for data on them all a little easier.

 

[royinidaho]

Good idea, Mike.

Just checked UPS and my scope is out for delivery. This rifle is the first one that I've ever owned that actually demands a decent reticle and accurate clicks. This one has both, at least for these tired old eyes.

By extraction marks do you mean marks on the case face?

I hear you on the temperature, plus you have air density working against you, but if there's a cartridge and bullet that will over come those obstacles, you have it.

That's quite a bearing surface on the 195, does it heat up the barrel anymore than the 169s or the standard bullets?

Hope to have something meaningful to post shortly.

 

[lerch]

Pretty good idea Mike, will definantly keep people from having to search all over hell for info.

Well here is the load i am currently using, it is also the load that got is still blowing holes in 3/8" steel at 910yds.

169.5 ULD
101.0gr US869
Fed GM215M primer
Loaded .002" off lands
Rem 7mm RUM brass
No real case prep

This load will group around 2.5" at 650yds pretty regular. This load is also VERY hot and I dont recommend it. I have not chronod it but when developing my drops out to 1K i used Exbals velocity tweaking controls and a speed of around 3500fps matches my drops, 14.5moa at 1K. This load is laser flat and hits with definate authority but I suspect case life will be around 4-5 firings. When I get my gun rebarreled next year i will be trying to get her to shoot the 169.5's around 3200fps or the 195 around 3000.

I have also found that my gun really likes it if you just keep the powder fouling out of the bbl. As long as i give the bore a quick scrub out every 25rnds or so she shoots great regardless of copper build up.

take it easy
steve

 

[hoghound]

Well here is the data I had in the other post. Figured I would move it here as well.

There is no way we can stuff 100grs. of H-869 behind the 169.5's down here 165 feet above sea level and get sane pressures. Hell I got 94gr. of 869 pushing the 169.5's a legit 3400fps with no signs of preasure but backed it back down to 92.5gr and getting 3280-3300fps. which shoots .123 at 100yds.

The 195's I have stoked with 94gr. of 872 clocking 3250-3300fps with no preasure and cut a .075 group.

I have both bullets loaded with 10k jump and she shoots great. Mike's rifle likes 15k jump better.

 

[41mag]

Roy,
The marks I was referring to are ranging from a slight shiny area which goes around the rim from 1/3 - 1/2 on the bottom of the case, a slight flowing into the extractor button, to some pretty nasty flowing and a definate bolt lift issue. These were things which I had to learn about in our area using the 869, and some of the loads others were using. I have since backed off to a 92.5gr load of 869 for the 169.5's and have absolutely no problems with pressures or case life. Some of the cases I am using have been loaded upwards of 8 times with this load and no loose pockets so far. This load gives me 3260 +/-fps depending on the temps at the time and groups well under MOA at all ranges I have shot it to 1150yds.

The 195gr load I have uses 94grs of 872, and is rocking along around 3150 fps. from my rifle. This is a top end load and when the temps hit above 95 degrees I start to feel some resistance in bolt lift. However, under 90 degrees it has not been an issue, even using some of the previous mentioned cases. All bullets for this rifle are seated to a base to ogive OAL. This keeps my distance from the lands at an even distance.

These loads are top end and if you use this data, please back down at least 5 grs and work up. Either of these powders will work great in this caliber and case combo, but you will have to determine your own upper limits. Mine were decided by picking a velocity and working towards it. I wanted a good velocity but didn't necessarily want to burn out the barrel in short order. I figured that mid-3200's was sufficient for anything I would be shooting, and when I hit that range, I started playing with other things.

For seating depths, I started on the lands, and worked out to .050" off. I noted in my barrel, that I increased copper fouling the further away I went. I also noted that I had passed up a node in my jumps and once I backed up some I hit the groups I was looking for. So for now, I am sitting roughly .015 off, and grouping great.

As for the bearing lengths, yes the 195's are some long puppies, and after shooting the 169.5's with the 869, that was one of the factors which leaned me towards the 872. I figured that I would get much better densities and less pressures using it. As for the sooty burn charactoristic, well it does deminish at the upper ends of the loads. With the groups I have gotten I can easily deal with it. As to the barrel heating up more with them over the others, I haven't really paid that much attention to it.

 

[wildcat]

Hey guys, I will soon be a the proud owner of a 338 Allen Mag. Is this group for a specific caliber of Allen Mag, or will it be for all Allen Mag owners. This sounds like it would be a good idea.

Wildcat

 

[Ridge Runner]

I have a 7 AM, my load is 110 gr of 872 behind a 160 gr nosler, this load is fine at 75 degrees and below, right at 3500 fps. tried it once at 90 degrees, couldn't get the bolt up. at 85 degrees got a heavy bolt lift and 3736 fps.
From my research I've found that the heavier bullet you shoot the less the temp sensativity effects it. I just shoot in cool weather.
the bullet is just off the lands and have shot a 1.875 group at 660 yds.want to give it a go at 1K when I get a good day.
JS

 

[41mag]

Wildcat,

I see no reason why it has to be caliber specific. The info posted here will hopefuly help someone get a better idea of things, before having to burn up compeoents and barrel life. Personally, I would much rather find and hit a load quickly, then spend the other time, learing to put these things to their true potential.

One thing mentioned in past threads is fire forming cases with cornmeal. Well I thought about is, loaded some up, then after spilling it everywhere, decided to just use bullets. It does work and does save barrel time, but for me, just wasn't what I was accustomed to. Luckily, the FF load I am using shoots excellent out to 500yd easily, and should be good much further for small game up to deer or hogs.

My FF load is 98grs of 872 under a 150gr Nosler Solid Base. I will be trying out the BT as soon as i pick some up to see if they shoot as well. IF so I will switch over to them. This load gets, low to mid 3400fps from my rifle and will group around 1" at 500yds. Cases are Remington 7mm RUM, necked down to the point I can just feel them touch when I close the bolt. There is about a 1/16" or so of neck that doesn't get sized. I have not sen any issues with pressure using this load up to temps of 98 degrees, and 100% humidity.

I will most likly end up using the 169.5's after I finish up with this batch of cases, for any future FF rounds. But that might be sometime next year. I have loads for everything and will most likly only be shooting a few here and there to maintain my skills at different ranges, and to hunt with.

 

[TMR]

Maybe add the case forming steps and pictures(how they should look) for forming the 270-338AM's.

I can't believe the velocities you guys are getting with the 270AM's......Now I am going to have to have one of them built once the 7mmAM is finished.

 

[wildcat]

Thanks Mike, this sounds like it will be a good place to search for Allen Mag info.

Wildcat

 

[41mag]

TMR,

"for forming the 270-338AM's"
Are you referring to the .277 AM or just forming all of the different cases in general from the .270 up thru the 338?

 

[TMR]

Maybe an overview of all the cases. Would maybe give everyone an idea of how to make them. Might save alot of questions down the road as popular as these cartridges are getting.

 

[hoghound]

I can't believe the velocities you guys are getting with the 270AM's......Now I am going to have to have one of them built once the 7mmAM is finished.

[/ QUOTE ]

TMR, I know where a 270AM can be had. You would have it most likely before you recieve your 7AM. Tim /ubbthreads/images/graemlins/grin.gif

 

[TMR]

[ QUOTE ]


I can't believe the velocities you guys are getting with the 270AM's......Now I am going to have to have one of them built once the 7mmAM is finished.

[/ QUOTE ]


TMR, I know where a 270AM can be had. You would have it most likely before you recieve your 7AM. Tim /ubbthreads/images/graemlins/grin.gif

[/ QUOTE ]

Tim.....been thinking about it. It is really the little woman that would like to have it for her new hunting rifle.