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Ok so I loaded up a test run of 8208 and 120 gold dots. The starting load was 23.2 and worked up in .2gr increments up to 25.0
I just received my Magnetospeed the other day and finally found some sunlight this evening to shoot it. I've never used a chrono before now so just seeing what you guys think on these results. The temp. dropped rather quickly this evening with a front blowing in and gusts up to 30mph. So here is what I got:
1- 23.2gr - 1971
2- 23.4gr - 1992
3- 23.6gr -1986
4- 23.8gr - 1978
5 - 24.0gr- 2004
6- 24.2gr - 2033
7- 24.4gr - 2085
8- 24.6gr - 2055
9- 24.8gr - 2059
10- 25gr - 2065
I'm wondering if my scale is not accurate enough. I just got a Ohaus beam scale in yesterday to use instead of my digital that I have always used. I've been using a digital Hornady scale that I've had for about 10 yrs. I just find it strange that from 2 to 3 it went down and again on 4 as well. The rest started climbing like it should. What's your thoughts here?
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Looks like underthrows too me.
A note on the magnetospeed. You can use it no matter the light are wind and weather, it's not effected by atmospheric conditions.
Also it should have come with some rubber shims. Use the one that allows the flat edge on top to be 1/4 to 1/8 of a inch below the bore hole. And readjust your sensitivity settings.
Also I wouldn't start that low again. Next time start at 25 grains.
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A5BLASTER Wrote:Looks like underthrows too me.
A note on the magnetospeed. You can use it no matter the light are wind and weather, it's not effected by atmospheric conditions.
Also it should have come with some rubber shims. Use the one that allows the flat edge on top to be 1/4 to 1/8 of a inch below the bore hole. And readjust your sensitivity settings.
Also I wouldn't start that low again. Next time start at 25 grains.
Yea that's why I chose this one after lots of research. Weather in Va ....if you dont like it wait until tomorrow...lol
I used the smallest rubber shim it came with. It actually fit perfectly. I had no issues with it at all...knock on wood.
I'm running it in my AR so I started at the low end of the chart and worked up just to see. I had no pressure signs at all at the end so I might go a tad higher next time.
I have another set already loaded with TAC but my fingers got too cold to run it. The field was too wet to drive so I had to walk to my shooting range.
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Daveycrockett Wrote:Yea that's why I chose this one after lots of research. Weather in Va ....if you dont like it wait until tomorrow...lol
I used the smallest rubber shim it came with. It actually fit perfectly. I had no issues with it at all...knock on wood.
I'm running it in my AR so I started at the low end of the chart and worked up just to see. I had no pressure signs at all at the end so I might go a tad higher next time.
I have another set already loaded with TAC but my fingers got too cold to run it. The field was too wet to drive so I had to walk to my shooting range.
I don't start anything lower then 25 grains. Just seems like a waste of product. Considering the vast majority of powders used in the grendel end up in the 27.5 to 30 grain range for loads.
Don't go over 28.5 with 8208. For what its worth I don't use 8208 and never will but 28.5 is a well established max on this fourm for 123 to bout 100 grain bullets.
I'm in love with ar-comp,h4895 and h332. Planning on getting rid of all my other powders.
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1971fps seems slow for a grendel
It looks like a defective Magnetospeed or low battery, can you try a factory round that has a publish velocity and see if you get a reading that is close to expected velocity, factor in your barrel length.
I would do .1 increments up to 25.0, Speer load data has 8208 much lower that other companies' 120gr and 123gr bullets, they go up to 28gr.
I have seen drops like that in ladders tests.
At the end of this thread is a ladder chart showing drops.
http://www.65grendel.com/forum/showthrea...ight=jimla
The drops often note a location of accuracy point.
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A5BLASTER Wrote:I don't start anything lower then 25 grains. Just seems like a waste of product. Considering the vast majority of powders used in the grendel end up in the 27.5 to 30 grain range for loads.
Don't go over 28.5 with 8208. For what its worth I don't use 8208 and never will but 28.5 is a well established max on this fourm for 123 to bout 100 grain bullets.
I'm in love with ar-comp,h4895 and h332. Planning on getting rid of all my other powders.
I picked up some AR comp as well but haven't opened it yet.
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I know manufacturer and bullet manufacturer info on MV can be "off" but for reference, the #15 Speer manual gives their minimum 8208XBR load of 22.9 grains under a 120 Gold Dot at 2210fps. I would imagine that ladder study is reading way under what was actually fired.
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Rosecrans1 Wrote:I know manufacturer and bullet manufacturer info on MV can be "off" but for reference, the #15 Speer manual gives their minimum 8208XBR load of 22.9 grains under a 120 Gold Dot at 2210fps. I would imagine that ladder study is reading way under what was actually fired.
It's possible but I belive it's because his barrel is making way under pressure for charge compared too book data he was following.
I belive he he started over at 25 and work up to 27.6 in 2 tenths he will see much more in line speeds for the grendel with that combo.
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Is that data in the OP representative of one round at each charge weight or an average of three or five? If singles, I'd say it's real and just showing the variation in the load. It would be pretty normal to have some overlap in ES with charges that close together.
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What barrel length do you have? If it is something under a 16" then maybe those velocities would be in the ball park but if 16" or longer they are way off. Like has been said you powder charges are Way too low. It has been my experience that Speer's load data for the 120 Gold Dot is WAY CONSERVITAVE. I did a work up with IMR 8208 with the 120 GD in two ARs. One has a 20" BCA barrel the other an 18" Oden Works. I used Hornady cases. CCI 450s and found that 28 grs was max before slight ejector swipes started to show on a couple cases pressure. 28 grs is where both of my rifles wanted to shoot this bullet the best. 20" average 2550 fps 18" 2500 fps this is from a number of range trips and weather conditions.
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Im shooting a 18 inch grendel hunter.
Starline brass twice fired
Cci 400 (what i have on hand)
Oal 2.260
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Daveycrockett Wrote:Im shooting a 18 inch grendel hunter.
Starline brass twice fired
Cci 400 (what i have on hand)
Oal 2.260
I would try and get some cci450's.
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I would up the powder charge.
My 12in Grendel shoots the 120gr Speer Gold Dot at 2230fps with the charge mentioned by 1Shot.
My 18in Grendel launches a 123gr ELD at 2465fps. Both of these with IMR8208.
You have room to play, and I would also change primers to a harder cupped one as suggested by A5.
SY
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I just got out to shoot my first 120 GD today, with 8208 and AR comp.
I ran both of these from roughly 26.5-28.
No chrono data, but 26.8,27.1 and 27.4 with 8208 were very accurate. Brass looked great, as well as the primers.
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The Hornady scale I started with was shamefully bad. I called them, they sent a replacement that worked well for about a week. Then it too went the way of the trashcan. I didn't call them a second time. Having done research after the first one quit putting out, I discovered I wasn't alone in my opinion of the scale... Search Hornady scale review, then Hornady auto charge review. Have fun.
I now use a cheap digital I found on Amazon, and verify daily with my Dillon beam. So far, it's fine. All you need is consistency, and a beam scale will tell you if you're digital is off. The digital is faster, or I'd just use the beam exclusively.
Nothing kills the incentive of men faster than a healthy sense of entitlement. Nothing kills entitlement faster than a healthy sense of achievement.
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120 gold dot didnt do very well on top of 8208 for me about 1? is all I could get.
120 GD 29g Ar comp is .35 at 100yds at 2530
