450Bushmaster.net

OK, I guess what I could use help with the most is: where to start!

I currently have a Bushmaster A2 in 5.56/.223. I've always had a preference for a caliber OTHER than this (perhaps 9mm to keep my calibers simplified), but I also like the idea of using this platform as a hunting rifle. Recently, I stumbled upon an ad on a forum where a local guy in the DFW area wanted to trade his .450b upper for a .223 upper and this sounded like a prime opportunity for me!

So, I'm jumping on this opportunity...supposed to meet the guy tomorrow to make the swap.

I've spent several hours browsing the net over the last day or so researching what I can on this new round, but I still have a few questions.

It doesnt sound like there's any 1 "perfect" method for dealing with the magazine, is there? My preference would be to use/modify the PMag's as I have about 25 of those in the gun safe, however, I'd feel most comfortable with an out-of-the-box method that works...something requiring little, if any, modification. I read that the Sig 556 mags seem to be the best w/o modification and may be on sale at Academy sports in a 2 pack.

I've also read somewhere that there may be a need to change out an existing spring and buffer in my lower to something heavier. Is this true? If so, where should I look?

Switching to a flattop upper, I have no idea where to even start looking for scopes...I'd prefer (for now at least) to keep cost at a minimum...any suggestions?

Any other ideas, suggestions, thoughts, tips or tricks I should know about as a beginner?

I guess I should mention that I dont currently reload and have absolutely zero experience with it, HOWEVER, have thought about doing it for quite some time now and may use this caliber as my excuse to start.

I look forward to any input you guys have to offer and thanks in advance for your help!
Steve

DrPhil wrote: My preference would be to use/modify the PMag's as I have about 25 of those in the gun safe, however, I'd feel most comfortable with an out-of-the-box method that works...something requiring little, if any, modification. I read that the Sig 556 mags seem to be the best w/o modification and may be on sale at Academy sports in a 2 pack.
Steve

The sig 556 seems to be the most popular, but I've heard bushmaster is offering a 9 round mag, although it's not on their website yet.

Welcome to the site Steve! I'm relatively new here as well, but I think you came to the right place. The folks here are most helpful.

DrPhil wrote:OK, I guess what I could use help with the most is: where to start!

I currently have a Bushmaster A2 in 5.56/.223. I've always had a preference for a caliber OTHER than this (perhaps 9mm to keep my calibers simplified), but I also like the idea of using this platform as a hunting rifle. Recently, I stumbled upon an ad on a forum where a local guy in the DFW area wanted to trade his .450b upper for a .223 upper and this sounded like a prime opportunity for me!

So, I'm jumping on this opportunity...supposed to meet the guy tomorrow to make the swap.

I'd jump on it too... sounds like a no brainer to me. You'll now have a Bushmaster Thumper upper to go along with a Bushmaster lower.

DrPhil wrote:I've spent several hours browsing the net over the last day or so researching what I can on this new round, but I still have a few questions.

It doesnt sound like there's any 1 "perfect" method for dealing with the magazine, is there? My preference would be to use/modify the PMag's as I have about 25 of those in the gun safe, however, I'd feel most comfortable with an out-of-the-box method that works...something requiring little, if any, modification. I read that the Sig 556 mags seem to be the best w/o modification and may be on sale at Academy sports in a 2 pack.

Its been reported on these very forums that Cammenga "easymags" work well with the .450 Bushmaster rounds. I've been meaning to pick some up for .223 use, but if they work with the .450, even better.

DrPhil wrote:I've also read somewhere that there may be a need to change out an existing spring and buffer in my lower to something heavier. Is this true? If so, where should I look?

I've read that elsewhere too but our very own Mudbug says he's slapped a .450 upper onto a standard lower without any changes and the rifle functions fine.

DrPhil wrote:Switching to a flattop upper, I have no idea where to even start looking for scopes...I'd prefer (for now at least) to keep cost at a minimum...any suggestions?

I know of many people who spend more on optics than the rifle they are mounting it on... glad I'm not one of those. I started with an inexpensive red dot (BSA) and then to a Leupold 2x7 UltimateSlam (blackpowder) scope. I chose the Leupold because it advertised itself with a BDC (Bullet Drop Compensated) reticle that had the same ballistics as the Hornady factory load 250gr projectile @ 2200fps. The scope was purchased for $230.00 and I am very pleased with it. Just make sure whatever you choose, that there is plenty of eye relief... scope eye (or scope brow) looks painful.

DrPhil wrote:Any other ideas, suggestions, thoughts, tips or tricks I should know about as a beginner?

I guess I should mention that I dont currently reload and have absolutely zero experience with it, HOWEVER, have thought about doing it for quite some time now and may use this caliber as my excuse to start.

Reloading is a seperate hobby onto itself... I'd highly recommend it and will pay for itself in the long run (that's what I was told when I first considered reloading). Actually, you may end up like me and my friends who reload... we didn't save any money... but for the same money we shoot a WHOLE LOT MORE.
Thankfully, the .450 Bushmaster is a straight walled (or is considered one) cartridge and reloading for straight walled cases is easier (IMHO) than reloading for bottlenecked cartridges. While the .450 Bushmaster isn't as expensive as some of the other "Big Bore" AR calibers, you're going to be paying $23-$29 for a box of 20 cartridges. I've got a favorite load I assemble for general plinkiing... that I estimate costs me $0.45 per round. That price will come down if I can find similar bullets cheaper... or if I use less expensive bullets.

BTW... WELCOME to the forums!

I may need to update my post about the lower I used. I think I might have a 9mm buffer in that lower (it's my 3gun rifle, and I think there is a heavy or 9mm buffer in it).

However, from everything I've read from Bushmaster the upper is made to just swap to your existing lowers. One of their selling points is that you have one rifle (the lower) that can swap between different calibers.


As far as an inexpensive scope see if look at the little Weaver 1-3x20 Classic V. I have one on my light weight 223 AR that I use for hunting javelina and coyotes.

MudBug wrote:I may need to update my post about the lower I used. I think I might have a 9mm buffer in that lower (it's my 3gun rifle, and I think there is a heavy or 9mm buffer in it).

However, from everything I've read from Bushmaster the upper is made to just swap to your existing lowers. One of their selling points is that you have one rifle (the lower) that can swap between different calibers.


As far as an inexpensive scope see if look at the little Weaver 1-3x20 Classic V. I have one on my light weight 223 AR that I use for hunting javelina and coyotes.

Shore is, just do the swap and bushy does have their 9 rounder out, so that a cure, but the conversion of you existing mags is straight forward and easy. AND me too, WELCOME and you definitely came to the right site, these guys will take care of ya..

Great leads guy...thank you VERY much and I appreciate the warm welcome. Hopefully the exchange will work out tomorrow as planned. I'll let you know and then we'll see where we go from there!

I have sucessfully converted 2 pmags to date and they are working 100% so far... I like the idea of the pmags because 'they are pmags' and durable as all get out..

It does take a little work (30 min or less) and a little tweaking to make sure the last round doesnt hang under the feed lips.. But I think they will last a long time..

congrats on the new upper..

Brian

made the swap today...the upper's mine! very nice seeing that LARGE diameter bore on this rifle!

i will say the mags included were certainly nothing special. the "5 round" mag, holds 4 at best...if you drop in a 5th, it fights the feed lips, trying to spread them as the round works halfway up out of the mag. by doing that, it spreads the top of the mag just enough to make it too tight of a squeeze to fit in the magwell. so, i'm wondering if i need to slightly bend the lips in.

i'm also wondering if the Sig 556 mags may be the easiest solution for now. i have several days off at the end of this week, so maybe i'll break out the dremel, a pmag and read over the thread on magazines.

it baffles me that they charge $9.95 for the proper follower for the GI mags...i mean, what's the standard 223 version of that part cost, maybe $1?

the current plan is to take it out for a range day friday, so we'll see how the mags work during live-fire.

I had a little trouble with the "standard" bushmaster mag that shipped with the rifle, but i bought a couple of the stainless mags from bushmaster, and have had no problems at all.
My favorites are the sig 556 mags. NO trouble what so ever out of the box, and the polymags dont leave marks on my brass. Just my 2 cents.

Congrats on the upper, and welcome to the world of 450B!!!!
You wont be dissappointed!!