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HerkyBird
02-14-2014, 04:44 PM
I'm thinking my Mini G would be even more Bravo Alpha with a CASM mount and a Leupold Mark 6 1-6x20. Does anyone have any experience with the holbrook device? Aside from the extra steps of pressing the clip latch and having to close the action, is it difficult to insert an already loaded en bloc underneath that mount?

jbkf1003
02-14-2014, 05:37 PM
I don't believe you can insert a full clip. You insert an empty clip before you install the mount, and you load that with single rounds. The empty clip stays in there semi-permanent. I think you can remove it / reinsert it from the bottom by removing the TG if needed.

See:

http://www.youtube.com/watch?v=MZ1WtDghxbg

I believe Tim just just modified an oprod catch on this rifle, but it's all but the same thing as a Holbrook Device.

HerkyBird
02-19-2014, 01:05 PM
Well that ruins that idea. Guess I'll just have to get a .308 mag-fed Mini G.

jbkf1003
02-19-2014, 01:30 PM
Yep that's where I'm at.

HerkyBird
02-19-2014, 01:37 PM
Or do the Ultimak, which would be a considerable cost and require a LER scope. I just like the en bloc system better.

jbkf1003
02-19-2014, 01:56 PM
Me too, I have an ultimak that's going to go on one (30-06 enbloc fed). I think it's getting an eotech. I'll be putting a 3-9x nikon with a casm mount on a 308 mag fed...

HerkyBird
02-19-2014, 03:47 PM
I have thought about sending my Mini G back to Shuff to get an Ultimak put on, but it'll cost me nearly $400 to do so. If I did, I'd probably go with an Aimpoint or Eotech like you're planning to do. I should've just sprang for the extra $285 and had him do it when he did the conversion, but I didn't. Hindsight and all that.

jbkf1003
02-19-2014, 03:58 PM
Herky, Just get a drop down BM59 drop down gas cylinder from standard parts and the muzzle brake to match. Have Tim install this and straighten your oprod to work on the new cylinder (Tim tells me there is some small risk to the rod doing this, but hey life is about risks). Then you can install the Ultimak rail yourself without having to mill it or the oprod. I don't know if it's much cheaper, but you don't have to modify the oprod or the mount. The drop down cylinder gives you the clearance you need to install the rail. That way you can always take it off if you need and your oprod is not modified.

Plus drop down gas cylinders are cool.

Mine's at Tim's now for this modification.

Justin

HerkyBird
02-19-2014, 04:43 PM
Tim...If you're listening...What are the risks and what would it cost...ish.

jbkf1003
02-20-2014, 10:40 AM
Herky,

For what it's worth. I installed a holbrook device in my fullsize 308 last night. I tried to load it with a captivated enbloc clip. It's not real fun. It's hard to get the base of the cartridge all the way back (I had to push a few rounds back by the tip), and getting the 8th round it was a bit challenging. This is without a scope rail on it too. Tim makes it look a lot easier in his youtube video. With some practice it might get better. I just tried one time and said forget it...

If you were going to load it up once and sit in a treestand all day and maybe take a shot or 2. It's probably fine, but if you wanted to shoot it more that that, I would think it's not the way you want to go. Go Mag Fed if you want a center mount scope, and you intend to use the rifle for more than hunting.

This is not to disparage the product in general, in fairness to Mr Holbrook this was not what it was designed to do. It works fine for it's intended purpose of not automatically ejecting a spent clip, and not automatically closing the bolt when you insert a new clip.

Justin

timshufflin
02-20-2014, 06:01 PM
Hmm, I've never had a problem loading a full enbloc into a garand with a holbrook.

Risk to oprod when straightening, it's a small risk but the rod could break at a curve. Remember, a Mini-G rod has already been bent twice and the inside of these rods aren't exactly pristine metal lacking rust.

Cost to convert a G to a straight rod is;
Parts you cover
Bend rod, new piston, slightly shorten, park, $100
Re assemble, test fire $70
Shipping as listed on my site.

jbkf1003
02-20-2014, 06:17 PM
Tim,

It was a empty clip held into the rifle by the holbrook, then loaded to 8 rounds manually one at a time. To simulate how it would be to load with a CASM mount. I'm sure it would get easier with practice, but I decided magfed as the way to go if using a CASM mount.

Justin

timshufflin
02-20-2014, 06:33 PM
Oh, now I got you. I never top of a clip that's already loaded, that's too tough.

loboft
04-14-2014, 11:33 AM
I have the Holbrook device and CASM mount on my mini G. When the CASM mount is on, you do indeed have to single load your rounds. Hasn't been an issue for me, but each to his own. When the CASM is not installed, and regular rear sight aperature is used, you can eject and reload enblocs by pushing the eject button. Hope that helps.

jbkf1003
04-14-2014, 03:08 PM
Thank you sir, I decided to go Mag Fed... :)