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7/16/2008 11:15:40 AM EDT
Hey guys.... I just got a Blackthorne 24" varmint and took it to the range. I used 68 grain bullets and got a 12" spread at 100 yards!!! I have a BSA scope. If it's not me, what's the problem? Thanks,
7/16/2008 11:27:14 AM EDT
[#1]
My first guess off the little tiny bit of info you gave would be that you are using to heavy of bullets for the rate of twist in your barrel.

The second would be the BSA scope.

If you have a 24" varmint barrel with a 1-12 twist  you should be shooting a lighter 40-55 grn bullet
7/16/2008 11:38:25 AM EDT
[#2]

Quoted:
12 Inch Spread? Help!

Tell your wife/girlfriend to lay off the bon-bons.

(kidding!)

My first guess was going to be the BSA scope, but feel free to take the above advice over mine.

If/when you get to the scope, see if someone will let you borrow their scope to compare (or use another, if you have one).

Just like with computers and cars, it's all about isolating one variable at a time.
7/16/2008 12:06:58 PM EDT
[#3]
Thanks for the help guys. It's a 1/9 twist... if that means anything.
7/16/2008 12:34:40 PM EDT
[#4]
I have always had good results with 68 and 69 grain bullets in 1:9 twist.

As a previous posted suggested, isolate one variable at a time.
7/16/2008 12:42:11 PM EDT
[#5]
I vote for the scope and or mounts.
7/16/2008 12:45:37 PM EDT
[#6]
What's your 20?

You can provide general region if you prefer not to say specifically (i.e. greater DFW metroplex area, greater Corpus Christi area, etc).
7/16/2008 12:56:25 PM EDT
[#7]
Check your rings/mounts and zero at 50 yards.
7/16/2008 1:19:58 PM EDT
[#8]
1) blackthorne kit
2) twist vs ammo
3) scope/mount
7/16/2008 1:38:56 PM EDT
[#9]

Quoted:
1) blackthorne kit


Hate to agree, but with this company sometimes you win, sometimes you lose.

Technically, you're using the correct bullet weight for the twist-rate.  Unless you got unlucky with BSA, I'd blame the upper before blaming the scope.

Have you talked to anyone at Blackthorne?

C97
7/16/2008 4:45:24 PM EDT
[#10]
I would do as some of the others have suggested, and check tightness of scope mounts.  

Then considering that it is a Blackthorne upper I would make sure the barrel is attached tightly to the receiver.  Also, may wan tto make sure there is a barrel index pin installed in the barrel extension, or that it hasn't bent or broken.  Blackthorne has been knon in the past to use a roll pin instead of a solid steel index pin.

Then I would check the scope for problems.  
Ihave used a couple of BSA scopes and had no problems, but I have heard of others  having problems.

You may want to do this in a short ammount of time becasue if I recall correctly Blackthorne only offers a 36 or 48 hour warranty for you to try and find a problem with their product.

Sorry to be a bearer of bad news about Blackthorne, but that is why they are more "affoardable".
7/17/2008 8:34:48 AM EDT
[#11]

Quoted:

Then considering that it is a Blackthorne upper I would make sure the barrel is attached tightly to the receiver.  Also, may wan tto make sure there is a barrel index pin installed in the barrel extension, or that it hasn't bent or broken.  Blackthorne has been knon in the past to use a roll pin instead of a solid steel index pin.


What is a "barrel index pin"? Sorry for my ingnorance.
Also... I realize Blackthorne is less than perfection. But a 12" spread? That seems a little too large to blame on the upper alone... or so I guess. I checked the scope mounts and found that, although I could get them slightly tighter, they were already pretty snug.

As far as my location, I'm in TX... near Houston.

Thanks for all the help guys.
7/17/2008 8:42:28 AM EDT
[#12]

Quoted:
As far as my location, I'm in TX... near Houston.

In that case, you might be well-served by visiting the Texas Hometown Forum (TX HTF) and asking one of the Houston Crew.

Trust me, there are a metric shit-ton of Texas arfcommers from the Houston area.

I'm sure there are at *least* a few who shoot at your regular range, and who could be convinced to meet you there one day and let you swap optics/mounts.

Another variable-reducing option would be letting them shoot with your optic/mount combo.

If it works fine on their rifle, that's probably not it.


ETA: link to TX HTF
7/17/2008 1:09:47 PM EDT
[#13]

Quoted:

Quoted:

Then considering that it is a Blackthorne upper I would make sure the barrel is attached tightly to the receiver.  Also, may wan tto make sure there is a barrel index pin installed in the barrel extension, or that it hasn't bent or broken.  Blackthorne has been knon in the past to use a roll pin instead of a solid steel index pin.


What is a "barrel index pin"? Sorry for my ingnorance.
Also... I realize Blackthorne is less than perfection. But a 12" spread? That seems a little too large to blame on the upper alone... or so I guess. I checked the scope mounts and found that, although I could get them slightly tighter, they were already pretty snug.

As far as my location, I'm in TX... near Houston.

Thanks for all the help guys.



blackthorne is not less than perfection

blackthorne is the absolute worst you could possibly buy.
7/17/2008 1:48:39 PM EDT
[#14]

Quoted:
1) blackthorne kit
2) twist vs ammo
3) scope/mount


This is what I'm thinking.
7/17/2008 3:52:00 PM EDT
[#15]

Quoted:
blackthorne is not less than perfection

blackthorne is the absolute worst you could possibly buy.

Isn't that also the name of the security contracting firm from "The Unit"?
7/17/2008 4:55:55 PM EDT
[#16]

Quoted:

Quoted:

Then considering that it is a Blackthorne upper I would make sure the barrel is attached tightly to the receiver.  Also, may wan tto make sure there is a barrel index pin installed in the barrel extension, or that it hasn't bent or broken.  Blackthorne has been knon in the past to use a roll pin instead of a solid steel index pin.


What is a "barrel index pin"? Sorry for my ingnorance.
Also... I realize Blackthorne is less than perfection. But a 12" spread? That seems a little too large to blame on the upper alone... or so I guess. I checked the scope mounts and found that, although I could get them slightly tighter, they were already pretty snug.

As far as my location, I'm in TX... near Houston.

Thanks for all the help guys.


You would have to take the barrel nut off of teh barel to find out for sure if the index pin was correctly installed, the correct pin, and not broken.  If you take a look in teh stickies above, the section on replacing a barrel or installing a freefloat tube will have pictures that show the index pin aligning in a notch in the upper receiver.  This should be a solid steel pin that holds the barrel in alignment with the barrel extension and with the receiver itself.

Small part, but it's important.

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