450Bushmaster.net

I got out to shoot the 450 at 100 yards yesterday. I had a few factory loads and shot those first. Pretty good groups then the handloads. Way high and left from factory. I loaded 35 grainf of 'Lil Gun with 250 gr Hornadys. Once scope adjustments were made I'm very happy with the accuracy. The pic shows the last group I shot. Two mags as quick as the range allows. No real rapid fire but about one shot every 2 seconds.
One mag works fine, one I get the jam pictured at least once per magful and the mag that came with the upper jams all the time. All Bushmaster SS mags. I'm going to measure the lips with a caliper and try to adjust them to match the mag that works.

Speed them up and the POI will come back to center. Why so light (35gr)? 38gr will get you very close to factory performance with a taper crimp in the area of .476 and a hot primer like WSR, Rem 7 1/2, or Fed GM205M. No CCI 200 or BR4. They're too light.

Hoot

I always start reloading a new cartrige with a light load. I'll go up to 38 grains though. I'm using WSR Primers with the crimp at 476 as recommended so with the change of powder weight, I should be good to go.

I had similar problems with jamming on my first and second outings - would get at least one stove pipe with the next round trapped under it (as per jeepjeep's photo). On my third outing, I went out prepared for extensive data taking on which round in the sequence on which mags was jamming, but had only one problem out of 100 rounds. They were all BM SS 5 round mags. Maybe they just need to be "run-in" a little? There is some discussion on jamming problems here - http://450bushmaster.net/viewtopic.php?f=2&t=741&p=14380&hilit=jamming+stovepipe#p14380.

There is another thread with photos and other comments. Also, many have recommended the sig polymer 30 round (.223 / 5.56) mags loaded with 11 or 12 BM450 rounds as a good alternative. I picked up two at Academy for cheap, modified the followers (see http://450bushmaster.net/viewtopic.php?f=2&t=4175, but have not shot them yet. Here is one thread - http://450bushmaster.net/viewtopic.php?f=2&t=4754&start=10

I know about the SIG mags which are illegal in NY at least unless they have the 450 follower and a block installed to make them 10 round only. I hate NY for so many reasons!
Thanks for your sugestions. Maybe they need a break in period but I will measure the feedd lips to see if that may be the problem since the one mag is fine.

Jeep, It pains me to see you deal with all of the NY bull. You truly seem to be a fish out of water... Loving what you can't have.... Like Lindsay Lohan in prison

Hoot wrote:Speed them up and the POI will come back to center. Why so light (35gr)? 38gr will get you very close to factory performance with a taper crimp in the area of .476 and a hot primer like WSR, Rem 7 1/2, or Fed GM205M. No CCI 200 or BR4. They're too light.

Hoot

Lite, and they could be short-stroking, because they are so lite, hence the stove-pipe, and/or, did we properly clean the shipping oils from the weapon, inside and out, how about proper lubrication? These things are vital, but more than likely the Hoot has a better track on the problem, just a thought..t

Light?....Sooting doesn't go away until you hit 40grns. of Lil Gun.
Then your starting with a good clean burn. "IMHO"

bushmeister wrote:Jeep, It pains me to see you deal with all of the NY bull. You truly seem to be a fish out of water... Loving what you can't have.... Like Lindsay Lohan in prison

Thank you for the sympathy...I think lolol!
Yes, I cleaned it really well and lubed it good as well. I will be measuring the mag lips tomorrow just to see what's what (I've been away) and after that I'll hope things will get better with 38 grains of 'Lil Gun. I can go as high as 40 Grains safely? I really need to get a new Hornady loading book!

OK, I just got a chance to measure the lips on the 3 mags.
The one that doesn't jam: 0.454 at the rear of the lips-0.472 at the front
One that jams once in a while: rear 0.451-0.467 front
One that jams a lot:rear 0.440-0.462 front
I see a pattern here. Tomorrow I'll try to adjust the bad ones to match the good one. What's the best way to open them up a bit?