Grendel Belted Magnum

[maverick5582]

[pds]

maverick,
You may want to consider this for adding weight to slow the BCG down. http://www.davidtubb.com/ar-15-carrier-weight-system

pds

[ricsmall]

Maverick,

Refresh me on your gas system. Is it rifle length with rifle buffer?

Richard

[maverick5582]

Maverick,

Refresh me on your gas system. Is it rifle length with rifle buffer?

Richard

Yes.

[ricsmall]

You should be fine with adjustable gas block. I think, going from memory, you should have an.0935 gas port and run fine with a 24", especially if you don't load too hot. I know bwaites had some trouble in his 28" and there may be others who had trouble with 24". I'm sure some others will chime in. The only downside to extra buffer weights is if you decide to load lighter projos, which may short stroke with the extra weight. Keep us posted.

[maverick5582]

You should be fine with adjustable gas block. I think, going from memory, you should have an.0935 gas port and run fine with a 24", especially if you don't load too hot. I know bwaites had some trouble in his 28" and there may be others who had trouble with 24". I'm sure some others will chime in. The only downside to extra buffer weights is if you decide to load lighter projos, which may short stroke with the extra weight. Keep us posted.

Gas port is .099"

[maverick5582]

maverick,
You may want to consider this for adding weight to slow the BCG down. http://www.davidtubb.com/ar-15-carrier-weight-system

pds

I have looked at the Tubbs system. It seems easier to me to mix and match weights in the buffer.

[Bwild97]

maverick5582, I too have a 24" barrel with a .099" gas port. I have installed a Wolff Extra Power spring, Tubbs CWS, and an adjustable gas block in hopes to eliminate the case head extrusions, and extractor swipes when handloading the Grendel with 8208 and 120g class projectiles. In spite of these efforts I still get swipes and an occasional extrusion even with lite loads of 26.5g of 8208 and non-magnum primers.

The Tubbs CWS is very easy to use. It slips right into the rear of the BCG, so do the two weights that it comes with (one is Tungsten the other is Stainless). you could always try mixing and matching the Tungsten and Steel weights in the CWS, provided you have a surplus of material to work with.

Is your Buttstock collapsible (carbine length tube)? If it is you may want to consider replacing it with a rifle length system. From what I have experienced in the past that long barrel, short buffer tube has always been a funky combo.

[maverick5582]

Tubbs CWS

maverick5582, I too have a 24" barrel with a .099" gas port. I have installed a Wolff Extra Power spring, Tubbs CWS, and an adjustable gas block in hopes to eliminate the case head extrusions, and extractor swipes when handloading the Grendel with 8208 and 120g class projectiles. In spite of these efforts I still get swipes and an occasional extrusion even with lite loads of 26.5g of 8208 and non-magnum primers.

The Tubbs CWS is very easy to use. It slips right into the rear of the BCG, so do the two weights that it comes with (one is Tungsten the other is Stainless). you could always try mixing and matching the Tungsten and Steel weights in the CWS, provided you have a surplus of material to work with.

Is your Buttstock collapsible (carbine length tube)? If it is you may want to consider replacing it with a rifle length system. From what I have experienced in the past that long barrel, short buffer tube has always been a funky combo.

I have a A2 buttstock with 2 lb. of lead in it to counter-balance the heavy barrel. I have looked at the Tubbs CWS and I need a little better understanding of the sleeve that holds the tungsten. Like how long the sleeve is and is it a blind hole for the weight. I know it has an .080" flange on it and I am assuming that it just slips in the carrier with no way to keep it attached to the carrier.

I have a lathe, milling machine, and TIG welder in my shop so I am use to fabricating many of my parts. I have seen other people use a 5/8" lead slug epoxied into the carrier. I have a spare carrier to work with so I can go that route if needed. I just need some idea of the total amount of weight involved. I had rather use Tungsten than lead because less will be needed to accomplish the job.

[Drifter]

I view the different buffer weights, carrier weights, and buffer spring strengths as ways to fine-tune a setup that isn't too far off to begin with. Instead of going to the extreme with these aspects, I suggest an adjustable gas block. If you need a 15-oz BCG and / or a 10-oz buffer to make things right, that should be a sign. Treat the cause (overgassed) instead of the resulting tell-tale symptoms.

[maverick5582]

Overgassed

I view the different buffer weights, carrier weights, and buffer spring strengths as ways to fine-tune a setup that isn't too far off to begin with. Instead of going to the extreme with these aspects, I suggest an adjustable gas block. If you need a 15-oz BCG and / or a 10-oz buffer to make things right, that should be a sign. Treat the cause (overgassed) instead of the resulting tell-tale symptoms.

I anticipated the need for an adjustable gas block when I chambered the barrel. I used an AA gas block and cut the Picatinny rail off the top in the milling machine to lower the profile, but left enough material to include a set screw. This is not the first time I have run into the overgassed situation in a gas-operated rifle. I have a re-barreled PSL that had the same problem. I appreciate the input.

[ricsmall]

+1 on drifters advice, gas block first, then fine tune if you need to with carrier weights.

[Bwild97]

maverick5582

I have a A2 buttstock with 2 lb. of lead in it to counter-balance the heavy barrel. I have looked at the Tubbs CWS and I need a little better understanding of the sleeve that holds the tungsten. Like how long the sleeve is and is it a blind hole for the weight. I know it has an .080" flange on it and I am assuming that it just slips in the carrier with no way to keep it attached to the carrier.

The Sleeve is sandwiched between the carrier and the buffer.

[maverick5582]

Carrier weight

The Sleeve is sandwiched between the carrier and the buffer.[/QUOTE]
Bwild97 Thanks for the info. I looked at a pic on DT website and worked out the dimensions. I tool a small piece of 3/4" stock and turned it to 0.625" with an .080" flange with a small 30 degree taper to match the photo as much as I could. It is 2" long and weighs 2.75 ounces. It slips into the carrier fine. I will keep it in my range box and slip it in the carrier when I try the XBR loads. I can always drill a 1/2" hole 7/16" long in the piece in the lathe with a 1/2" end mill and add tungsten if needed. You can buy tungsten in 1/2" x 7/16 pieces that are made for pinewood derby cars and only drill out as much steel as needed.

http://www.maximum-velocity.com/pinewood_derby_weight.htm#canopy