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12/28/2003 3:29:11 PM EDT
So I'm preparing to do some testing of heavier grain rounds in my 1/9 twist barrel to see what will and won't stabilize.  I know the ambient temp and humidity has an effect on this, but I'm not sure whether heat helps or hurts.  Any ideas?
12/28/2003 4:07:06 PM EDT
[#1]
Lower temperatures will make them harder to stabilize since cold air is more dense.
12/28/2003 4:07:07 PM EDT
[#2]
OK here is my $.02. With a 1/9 twist your going to top out in the 75 gr bullet weight,I think 77 is too heavy to stabilize and an 80 won't.
Heat will affect your loads the same way cold would. Max loads worked up in the winter will usually be too hot in the summer.  These are my findings when working up loads for my .223 bolt gun. An AR should be able to handle a little more pressure because it bleeds off to cycle the action and my results were with a 24" bbl.
Velocity will be a lil' slower in a 20". Hope this helps.
12/28/2003 4:24:07 PM EDT
[#3]
So basically, if I can get a round to stabilize this time of year, it should be good year round.  Thanks guys!
12/29/2003 8:40:21 AM EDT
[#4]
Quoted:
OK here is my $.02. With a 1/9 twist your going to top out in the 75 gr bullet weight,I think 77 is too heavy to stabilize and an 80 won't.
....
View Quote


Might as well keep you money.

77gr is just as likely to stabilize as its the same (or a tad shorter) than the 75gr Hornady OTM.

And length is the deciding factor - not weight.

If KW951 can stabilize the 75gr under his conditions then he should be able to stabilize the 77gr as well.
12/29/2003 11:42:31 AM EDT
[#5]
Quoted:
And length is the deciding factor - not weight.
View Quote


Correct, and the 77gr is actually [i]slightly[/i] shorter than the 75gr, meaning you  should have a better chance of the 77gr stabilizing.
12/29/2003 2:04:25 PM EDT
[#6]
But... the 77gr will generally have somewhat lower velocity, which brings them back to being about even.

-Troy
12/29/2003 3:38:00 PM EDT
[#7]
Quoted:
But... the 77gr will generally have somewhat lower velocity, which brings them back to being about even.

-Troy
View Quote


Quit using your dang common sense on me!
12/29/2003 4:19:42 PM EDT
[#8]
I was going to start a new thread but since you guys are on the subject, I think now would be a good time to ask.  I've been loggin on for awhile now and I haven't heard much talk about the 73 grain berger bullet.  Or any of theirs for that matter.  I may have not have been watching as closely as I should've though.  I know black hills loads the 73 grainers.  So what's the deal? In succession;

1. Does anybody use them or like them here?
2. Why no fragmentation experiments on it?
3. Didn't some of the Marines use them or still do for competition and like them? (I thought I read it in an article somewhere)
4. Are they shorter than either the 77 or 75?
5. If Troy says 2 grains changes velocity enough to change stabilization, wouldn't they be a little quicker than the two others?  Making them possibly a good choice?  

Any thoughts from the guru's would be welcome here.  Regardless of what is said I may still try a box to see how they do in my gun.  I'm getting ready to place an order for something, even if it's wrong.
12/29/2003 4:31:40 PM EDT
[#9]
Quoted:
I've been loggin on for awhile now and I haven't heard much talk about the 73 grain berger bullet.  Or any of theirs for that matter.  I may have not have been watching as closely as I should've though.  I know black hills loads the 73 grainers.  So what's the deal? In succession;

1. Does anybody use them or like them here?
View Quote

Don't use them (local guys carry the 75gr & 77gr but no 73gr)


2. Why no fragmentation experiments on it?
View Quote

IIRC Doc Roberts DID do some testing on them - they worked fine IIRC


3. Didn't some of the Marines use them or still do for competition and like them? (I thought I read it in an article somewhere)
View Quote

Yes they use them for competition from what I remember.  For 'duty' use some units are getting the Mk262 Mk1 (Pat Rogers covered this in a post on another forum)


4. Are they shorter than either the 77 or 75?
View Quote

Don't know haven't pulled them


5. If Troy says 2 grains changes velocity enough to change stabilization, wouldn't they be a little quicker than the two others?  Making them possibly a good choice?
View Quote

They are on the Doc's 'recommended rounds' list.  So if you like them - use them.
12/29/2003 4:39:51 PM EDT
[#10]
I don't know of anyone making military/5.56-pressure loadings with these bullets, but it would certainly be a good test.  And, if they worked well (mostly a factor of bullet construction, something I'm not familiar with in regards to the Berger bullets), then they might be just what the 1:9 folks need.

-Troy
12/29/2003 5:11:37 PM EDT
[#11]
I have had good success with 75gr Bullets in DPMS 1-9 upper 24" SS bbl.  Never tried 80gr's yet, and I say that with this behind it.  The 80gr Noslers work well out of my Rem 700P (1-9).  Yeah I know hard to believe, but they do!  I tried them as a lark!  And, well......

12/30/2003 3:05:57 PM EDT
[#12]
rn22723,

I'm not trying to be rude or nothing but, at what distances did you "try" these rounds at.  And did you do accuracy work or what.  I believe you, it would just be nice to know more details!!!!!!!  If you feel like posting them.  Group size, distance, fps, etc.  

Thanks for the replies guys.  Keep them coming if you have an opinion.  I think I'm going to buy some of the black hills just to see.  They have them in the reloaded and new.  

BTW, sorry kw951 if I changed the subject.  My 2 cents on your subject is just try them.  When I went on the berger sight they showed the 73 grain "suggested" twist being 1 / 9.  Hornady also states 1 / 9 for their 75 grainer bthp.  I'm not saying their 100 % right but I think you'd just have to try it.  If you want to get all technical you could try them at a bunch of distances, compare them to a load you know already shoots good, and post the data here.  I'm pretty sure a bunch of us would love to see the results!!!!!!!!
12/30/2003 6:57:02 PM EDT
[#13]
Another question that hasn't been asked is what ranges do you plan on shooting 75/77's etc with the 1/9 ? If your not shooting beyond 200 yds  stability problems most likely won't be noticeable. Shoot them at 600 yds in a little wind and you will see it !
12/31/2003 6:09:54 AM EDT
[#14]
As far as the 73gr Bergers, I used them last season at the 300 yard line in Highpower.  They stabilized just fine out of a 1/9 barrel, and I got good groups with them (open sights, during a match, so I don't know exactly how big, but I scored well enough).  

One thing about the Bergers that's different is that the jacket is "scored" with vertical lines.  They don't extend all the way to the bullet tip, but I would imagine that they would aid fragmentation.  

From the Berger website:

.224 CAL 73 GRAIN LTB
ID: 22-73 LTB
Category: Bullets
 
Length Tolerant Bullet
Recommended twist rate is 1/9
Ballistic Coefficient is 0.331
Boat tail


12/31/2003 6:42:27 AM EDT
[#15]
Quoted:
I'm not trying to be rude or nothing but, at what distances did you "try" these rounds at.  And did you do accuracy work or what.  I believe you, it would just be nice to know more details!!!!!!!  If you feel like posting them.  Group size, distance, fps, etc.  

Thanks for the replies guys.  Keep them coming if you have an opinion.  I think I'm going to buy some of the black hills just to see.  They have them in the reloaded and new.
View Quote


I use the 77 grn. SMKs in my CR6724 24" 1/9 long range AR. They are used in "F" class at the 600 yard line and I have shot them all the way out to 1000 yards (fwiw, my hot load goes sub-sonic between the 900 and 1000 yard line). I like shooting them as they are mag length and on a "good-air" day they'll hold 1/2 MOA out to 800 yards in MY rifle. The trick is "barrel length" (preferably 24", when twist is 1/9) and they have to be "smoking" (ie. red-line loads).

I have not had good luck with them in my 1/9 16" M4 uppers made by RRA or Colt (both chrome-lined), but they shoot sweet outta the DPMS 16" 1/7 M4.

They do shoot in the M4 1/9s, but only about 4-5 MOA at the 100 yard line, which, while is good enough for military work, not so good when compared to 1-1.5 MOA groups of Wnchester 64 grn. Power Points or PP+ handloaded rounds I like.

Mike
12/31/2003 7:04:03 AM EDT
[#16]
I'm definitely going test them out ... my big concern was that I'd test and find them to stabilize only to have them stop doing so as the weather warmed up.  Thankfully it works the other way, so this is the perfect time of year for a test.  Hopefully in the next month or so I'll be able to post some pics with test groups from BH 77gr, 75gr, 68gr, Win 64gr PP, XM193, and Q3131A.
12/31/2003 7:30:20 AM EDT
[#17]
The 75s are about the same size as the 77s now. At least the ones I have are.
12/31/2003 8:41:06 AM EDT
[#18]
I'm looking at picking up a rifle with a 24" bbl (RRA Varminter) and debating whether to get the 1:12 or the 1:9 twist.  I don't really need to stabilize the heavier bullets, way out there.  I have a perfectly suitable 7-mag for that stuff.
12/31/2003 6:55:08 PM EDT
[#19]
mr. wilson,  what velocity are you getting out of your redline load?  I thought people shoot them at 1000!!!!!  Way cool.  That must be some gun!!!!

e swanson, what loads do you use past 300?  What brand rifle do you have to compete with?  Do you need alot of stuff to get started in High Power?
1/2/2004 5:55:50 AM EDT
[#20]
Quoted:
e swanson, what loads do you use past 300?  What brand rifle do you have to compete with?  Do you need alot of stuff to get started in High Power?
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- I'm looking for a load to use past 300 yards now.  The range where I've shot all my highpower matches so far (2 years) is only 300 yards.  I don't reload, so I'm looking either at 77gr SMK's from Black Hills or 75gr Hornady's for a 600 yard load.  Probably go with the 75's because they have a higher ballistic coefficient, less wind drift.  

- I have a post-ban Eagle Arms lower with an upper that's been re-worked by John Holliger ([url]www.whiteoakprecision.com[/url] or [url]www.whiteoakarmament.com[/url]).  

- Here's a couple links to places with good info on what you need to get started in Highpower.  We also have a competition section here at arfcom where you can find lots of info.
[url=www.illinoishighpower.org]Illinois Highpower[/url]
[url=http://members.ync.net/konrad/]Konrad's Highpower Page[/url]
1/5/2004 2:39:15 AM EDT
[#21]
Quoted:
mr. wilson,  what velocity are you getting out of your redline load?  I thought people shoot them at 1000!!!!!  Way cool.  That must be some gun!!!!
View Quote


The 77 SMKs load I shoot are moving in the neighborhood of 2850 fps outta this rifle: [url]http://www.colt.com/law/car.asp[/url].

Understand there are plenty of fellas here that reach the 1000 yard line w/ an A2 20" Service Rifle, so doing it with a 24" barreled rifle ain't that big a deal.

Mike
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