luv2shoot
Junior Member
They are Modern Sporting Rifles! Not media acclaimed "assault rifles"!
Posts: 15
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Post by luv2shoot on Jan 19, 2015 15:55:28 GMT -8
I've seen the buckammo pdf load data and it it very informative. I'd like to hear from others on what they are seeing/ loading for their pet loads with a AR platform. Keeping OAL to max of 2.30. No bolt guns please. Just AR's. interested in 70 to 90 grain stuff.Myself I have found as I have informed you have to "drive" this round max.
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Post by GLSHOOTER on Jan 19, 2015 18:44:13 GMT -8
I have been shooting the top end ACCURATE ARMS loads and the Hodgdon data a great deal. I have also loaded ten rounds on the lands and ten rounds at 2.260. I found the velocities were fifteen feet higher on the shorties and the accuracy was 0.1" worse. Not enough to make any appreciable difference. I have found RL15 works very well in the heavier pills.
Greg
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luv2shoot
Junior Member
They are Modern Sporting Rifles! Not media acclaimed "assault rifles"!
Posts: 15
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Post by luv2shoot on Jan 20, 2015 8:12:03 GMT -8
Seating out farther would drop pressure though ,right? I did start loading at the max-plus data ( as was suggested ) and the gun came alive. Groups shrunk big time. No signs of excessive pressure ( primer visual ) 75 grn vmax. 1/8 bbl. Haven't ran chrony yet. 30 / 40 degrees here in WV on a warm day. Too cold for the extra setup stuff.
Other. I had a situation where I was using a compressed load( don't recall the powder) and found what ever I was doing caused the shoulder to bulge slightly. Just enough to cause chambering problems. I had a case guage made from my bbl maker and that solved that issue.
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Post by GLSHOOTER on Jan 20, 2015 9:21:52 GMT -8
Seating out farther would drop pressure though ,right? I did start loading at the max-plus data ( as was suggested ) and the gun came alive. Groups shrunk big time. No signs of excessive pressure ( primer visual ) 75 grn vmax. 1/8 bbl. Haven't ran chrony yet. 30 / 40 degrees here in WV on a warm day. Too cold for the extra setup stuff. Other. I had a situation where I was using a compressed load( don't recall the powder) and found what ever I was doing caused the shoulder to bulge slightly. Just enough to cause chambering problems. I had a case guage made from my bbl maker and that solved that issue. Yes and no. Think of a bell curve that is an upside down U. The base line is the higest prresure. Now the closest to the LEFT on your graph is the bullet seated way down in the case. Causing lower case room/.cpaicity. This is a high pressure thing with SOME powders. Others don't care if you squash/compress them. Now as you sea tthe bulleyt further out the case capaicity goes up causing a drop in pressure. The bullet has a nice long run to the lands effectively increasing the burning room. Presures drop more as you seat out. The bottom of the bell curve is the LOWEST pressure. Now as you get CLOSERR to the lands by seating out the bullet starts to engrave earlier and this takes energy and you get a rise in pressure as now you meet resistance. The closer to the lands the higher the presures until you MASX out. We see this in seating into the lands all the time. This would be the HIGHEST pressure. Basically it is a trade off as the bulet moves in and out. Few of us seat short unless forced to with big bullets that are overly long and then we must adjust. Most guys in most AR's can't reach the lands period out of a magazine. On the custom reamers BHW uses for our wildcats we purposely design them so the lands can be reached, or close to it, out of a magzine. We want to be able use bullets that jump a long ways or some that like to be up close and personal with the lands. The bulging case phenomena is not good. Better to avoid that. Your barrel chamber is the best gauge you will ever have for the final word in fit. Greg
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luv2shoot
Junior Member
They are Modern Sporting Rifles! Not media acclaimed "assault rifles"!
Posts: 15
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Post by luv2shoot on Nov 17, 2015 15:17:34 GMT -8
Back again. Haven't had the investigative shooting time that I'd like to had this summer. But been giving heck lately. LOL First off Greg, thank you for your plethera of accurate knowledgeable information. ( and sharing with us) A "GregWiki" if you. will. LOL I built two AR 6x45's . One a 1/8 18" McGowan SS Button-R 11degree ,no flash hider and medium length gas. The other is one of the Midway 20" 1/8 5r ( Liberty ?) barrel. I was hoping to use bullets in the 85-87 range. After my range trials and trying various brands of pills and powder (AA2230,8208,Varget,Tac,H335 , RL15 and more)both barrels won't shoot pills in that range worth a s--t! More like a pattern than group.Betcha Hillary had something to do with it. LMAO. Moving down to 70-75 showed a different story. Three shot 100 yds groups sub moa. Some .4 MOA. (75 grn Speer HP -8208) Tried even 55grn Nosler BT. both barrels .5 MOA. So I'm puzzled. I thought the faster twist would stabilize the longer- heavier bullets and thus my 1/8 purchases. I've read the various comments on 1/9 and 1/10. Wouldn't had thought I goofed on my twist selection but... While I can live with the accuracy I'm seeing from the 70 range it is not what I had in mind. I'd still like to have an 85-87 accurate barrel. Did't occur to me to get a barrel throated for mag length pills. Thoughts? Greg in WV
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Post by GLSHOOTER on Nov 17, 2015 19:28:18 GMT -8
Change bullet brands in the heavies if you haven't already. Those bullets will stabilize with a 1:10.
Greg
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luv2shoot
Junior Member
They are Modern Sporting Rifles! Not media acclaimed "assault rifles"!
Posts: 15
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Post by luv2shoot on Nov 20, 2015 19:22:40 GMT -8
Tried all kinds of heavies in the 80 to 87 range. Hornady,Nosler,Speer,Berger Sierra. I would had thought using the 223 twist mentality that the 1/8 would had worked. But do I need 1/9 or 1/10 to get a 80~87 grn to shoot well would you think? Greg
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Deleted
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Post by Deleted on Nov 20, 2015 19:42:42 GMT -8
Tried all kinds of heavies in the 80 to 87 range. Hornady,Nosler,Speer,Berger Sierra. I would had thought using the 223 twist mentality that the 1/8 would had worked. But do I need 1/9 or 1/10 to get a 80~87 grn to shoot well would you think? Greg Actually the perfect twist for the 80-87 grain bullets is a 1 in 12 twist. Those are tough to come by so I would go with a 10. There is no need for a 1 in 8 twist to shoot the bullets you mentioned. It even gets more confusing if you throw in seating the bullets at magazine length. The 6mm likes being as close to the riflings as possible. What is the length of the throat in your chambers? Or I guess a better question is, what is the COAL when the bullets are seated touching the lands?
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luv2shoot
Junior Member
They are Modern Sporting Rifles! Not media acclaimed "assault rifles"!
Posts: 15
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Post by luv2shoot on Nov 21, 2015 5:30:33 GMT -8
Thanks for the reply. I do have all the JAM & COAL data and will post. ( Lock & Load Comparator) Swamped right now. Deer season here in WV and stowing gear for the week. But just a couple. A Berger 87 VLD Hunting is jumping .134 with a VLD mag. .171 in a regular mag. Is there a favorable bullet jump distance (80~87) range for the 6x45? I read Berger's loading info instructions about touching lands,then backing off until the sweetspot is found. It's my practice to start with .030 off then move in either direction. Of course not always possible with COAL magazine loads. I try one variable at a time. Powder then COAL and then primers. Been using LC brass. I remember the issue with Remington and Winchester many years back with the 6mm vs 243. All about the twist rate. The 700 Rem's wouldn't shoot the heavies but fine dropping down in weight . Sorry got side tracked.
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luv2shoot
Junior Member
They are Modern Sporting Rifles! Not media acclaimed "assault rifles"!
Posts: 15
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Post by luv2shoot on Dec 16, 2015 11:04:38 GMT -8
Based on 2.260 the following jams: Speer Deep Curl 80gn .129 Barnes TTSX BT 80gn .128 Berger VLD Hunting 80 gn .179 Hornady VMAX 87 .269 I see I can squeeze a bit more than 2.260 using ASC SS mags. 2.28 to 2.30
I will be wanting then a. 1/10 or 1/12 bbl. But throat question to shorten jump as the above is a lot in my opinion. But the reason I'm here. Some darn good advice.
Does BHW offer 6x45 chambering with a shorter throat for the 80~90 gn pills? Replies welcomed.
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Post by GLSHOOTER on Dec 16, 2015 13:11:02 GMT -8
Based on 2.260 the following jams: Speer Deep Curl 80gn .129 Barnes TTSX BT 80gn .128 Berger VLD Hunting 80 gn .179 Hornady VMAX 87 .269 I see I can squeeze a bit more than 2.260 using ASC SS mags. 2.28 to 2.30 I will be wanting then a. 1/10 or 1/12 bbl. But throat question to shorten jump as the above is a lot in my opinion. But the reason I'm here. Some darn good advice. Does BHW offer 6x45 chambering with a shorter throat for the 80~90 gn pills? Replies welcomed. BHW offers only one throat size. That being said we ar shooting the snot out of the 87 Hornady HPBT. They and the Sierras don't mind the jump in the least. I shot a lot of Speer 70 TNT's and they have to jump more than a tad along with the 58 VMAX that is stellar n this one. Greg
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luv2shoot
Junior Member
They are Modern Sporting Rifles! Not media acclaimed "assault rifles"!
Posts: 15
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Post by luv2shoot on Dec 16, 2015 15:46:54 GMT -8
A quandary . R Johnson above "The 6mm likes being as close to the riflings as possible." And Greg is saying ( if I understand) a big jump is okay. Perplexed I am. Think I'll buy the better for my bullet size(80,85,87,90 grnr's) twist 1/10 bbl 6x45 and just see what it will do. Going barrel shopping.
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Post by GLSHOOTER on Dec 16, 2015 15:53:09 GMT -8
A quandary . R Johnson above "The 6mm likes being as close to the riflings as possible." And Greg is saying ( if I understand) a big jump is okay. Perplexed I am. Think I'll buy the better for my bullet size(80,85,87,90 grnr's) twist 1/10 bbl 6x45 and just see what it will do. Going barrel shopping. It likes being as close as you can get but that doesn't keep it from shooting with a jump. The same can be said about the 223 and 243 LBC and 6X6.8. That's why we recommend the ASC STAINLESS STEEL magazines that let you get as close as you can and not fret the jump. Sierras are world renowned for shooting up close and way out and that's one reason why they win so many HP matches. If a barrel won't shoot Green Box chances are it won't shoot anything else. Greg
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luv2shoot
Junior Member
They are Modern Sporting Rifles! Not media acclaimed "assault rifles"!
Posts: 15
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Post by luv2shoot on Dec 16, 2015 16:02:30 GMT -8
Amen on the ASC SS mags. I use them for about all my AR builds.
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