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jstultz
11-26-2011, 10:29 PM
Just ordered a mcgowen 16.5" ss varmint contour in 300 blackout for my model 10. was wondering if anyone has one? how does it group?

lskok
11-27-2011, 11:37 AM
Just ordered a mcgowen 16.5" ss varmint contour in 300 blackout for my model 10. was wondering if anyone has one? how does it group?

I have one. So far I am not too impressed, but I don't know what to blame. This is my first 300 Blackout so I do not have anything to compare to. I need to get some more time to get some real measurements but so far it looks like I'm shooting groups over 5" at 100 yards with factory Rem 220 subs.

jstultz
11-27-2011, 09:42 PM
that doesn't look good I hope you get it figured out, you would think it would shoot at least 1.5" good luck

GeorgeS
12-01-2011, 06:56 PM
I have one. So far I am not too impressed, but I don't know what to blame. This is my first 300 Blackout so I do not have anything to compare to. I need to get some more time to get some real measurements but so far it looks like I'm shooting groups over 5" at 100 yards with factory Rem 220 subs.


What twist is your barrel?

George

lskok
12-01-2011, 09:27 PM
What twist is your barrel?

George


It is a 1-8 twist. I went and shot a few rounds through it again today and I got groups under 3 inches. I have a factory trigger so I know that doesn't help. I'll be dropping in an SSS trigger to to see how that helps.

GeorgeS
12-02-2011, 02:23 AM
A 1-8" should stabilize those 220gr. bullets, as should a 1-10". What is your muzzle/instrumental velocity?

mbogo

lskok
12-02-2011, 10:57 AM
A 1-8" should stabilize those 220gr. bullets, as should a 1-10". What is your muzzle/instrumental velocity?

mbogo

I have not had a chance to chrono any yet. I had my chrono yesterday and forgot to bring my tripod to put it on!

memilanuk
12-02-2011, 09:07 PM
I don't think a factory trigger could be making the groups that big...

D.ID
12-04-2011, 12:06 AM
I got a 16.5" 1in8 varmint mcgowen in this caliber a couple months back and using 225 hornady match hpbt it shot under 1.5" right out of the gate even with 0.120 jump to the lands. I have not had time lately to do any more load development but I am sure it will do far better. That was with lake city mixed brass, cci primers and aa1680 2.26 OAL..........I recently acquired some proper remington brass but have not tested it yet.

sinman
12-07-2011, 02:17 AM
I have made quite a few 300 aac and 300/221fb barrels, I dont think I heard of one of mine that shot over 3/4", I would definitely question something if you are getting 5" groups

montana bob
12-07-2011, 08:57 PM
Scope Issues Maybe?

lskok
12-08-2011, 12:01 AM
Scope Issues Maybe?

Possible. This is used scope and has not gone on any other of my rifles. I really want to find a scope with some type of BDC that will work well with this round.

D.ID
12-09-2011, 02:17 AM
Mil dots "should" give 20 yard hold overs for subsonic 220 grainers but I would plan on dialing if your shooting farther than 200 yards with it, as it is really dropping fast. I am using a 3200 elite 10X and thinking about a 6x or 10x Swfa ss............I want to try and reach with it of course and figure I will need some long winded adjustments to pull it off.

helotaxi
12-09-2011, 07:05 AM
A 1-8" should stabilize those 220gr. bullets, as should a 1-10". What is your muzzle/instrumental velocity?


He's shooting subsonic Rem factory ammo so it should be in the 1040fps range. The BLK needs a 1:8 to reliably stabilize the heavy bullets at subsonic velocities.

Just an odd thought, but how is your follow-through on the shots? Figure the bullet is spending 2.5-3x as long in the barrel as you're used to. It could be that your technique isn't in sync with that. Similar reason that many people shoot AR type rifles worse than bolt guns, from the time the trigger breaks til the time the bullet leaves the muzzle is longer than they're used to and any slight flaw in their technique is highlighted.

lskok
12-14-2011, 04:07 PM
Ok, I decided my varmint contour is too heavy for me after I get the suppressor on it. I want something lighter so I decided to draw up exactly how I would like to have my 300 Blackout barrel built. I have submitted the blueprints to ER Shaw and I'm going to have them made. You can order one of these here for delivery in March:

http://www.gunshack.com/groupbuy?product_id=164

gopherslayer
12-14-2011, 10:30 PM
Ok, I decided my varmint contour is too heavy for me after I get the suppressor on it. I want something lighter so I decided to draw up exactly how I would like to have my 300 Blackout barrel built. I have submitted the blueprints to ER Shaw and I'm going to have them made. You can order one of these here for delivery in March:

http://www.gunshack.com/groupbuy?product_id=164



I take it the muzzle threads won't have a cap?

lskok
12-14-2011, 11:29 PM
I take it the muzzle threads won't have a cap?


That is correct so I guess I better order a bunch of .9" thread protectors.

gopherslayer
12-15-2011, 08:00 PM
Better set them up with the group buy then.

texasislandboy
01-30-2012, 06:32 PM
still want to get on this buy..

lskok
01-30-2012, 07:00 PM
still want to get on this buy..

I'm working on something so stay tuned and keep an eye out on the ER Shaw Blackout message thread.