450 Bushmaster Build

[H2OBUG]

I had an extra Savage Pawn shop pick up rifle as well as a Boyd’s Spike Camp stock I took off my 35 Whelen rifle. Paired it with a 18” Rhineland 450 Barrel and GLFA Brake. Swapped to a Tac Savage bolt. Did EGW base and MDT rings with a Budget SIG Scope. barrel and action are KG Gun Kote Statue Bronze.
We will see if this puppy shoots as good as my Ruger American did.

 

[357Mag]

I had an extra Savage Pawn shop pick up rifle as well as a Boyd’s Spike Camp stock I took off my 35 Whelen rifle. Paired it with a 18” Rhineland 450 Barrel and GLFA Brake. Swapped to a Tac Savage bolt. Did EGW base and MDT rings with a Budget SIG Scope. barrel and action are KG Gun Kote Statue Bronze.
We will see if this puppy shoots as good as my Ruger American did.

H2O -

Howdy !

What sort of load are you considering, to start with ?

That's a nice, thoughtful build !


Regards,
357Mag

 

[Cbashooter]

I just picked up a #1 450 bushmaster and the barrel is 1-10 twist. I've made taper/swage dies to take 350-450g 45-70 cast bullets down to .452-.454 and they chamber fine.So far i haven't gotten much under 2" at 100 yards but it's in early load development.
Keep us posted on your loads.i like the rifle you put together.

 

[Hoot]

Take a tip from someone who's spent the last 12 years perfecting 450b loads.
If you want to start off on the right foot, with ammo that's guaranteed to make you look good, consider the following recipe:
1F or new brass
225gr Hornady FTX
38gr Lil Gun
Rem 7 1/2 or other magnum primer,
Seated so that the cannelure is mostly buried below the mouth, with just a little of it showing and taper crimp down into the cannelure to a diameter of ,474 measured as close to the mouth as possible.
Produces 5-shot groups like this at 100 yds off of a good BR setup:



Not a max load yielding 2200fps but a Great morale booster!

Hoot

 

[lb-ft]

HOOT! That’s fantastic. There’s only one other I’ve seen get results like that with the 450, and they go by a very similar name on a different site
Tell me, have you found annealing brass after that first or second firing to restore accuracy to the load specified above?

Also, any proven Winchester 296 or Alliant 2400 loads, perhaps with XTP bullets? Or good budget loads with FMJ bullets? Love the cartridge but trying to both use existing supplies and bring the cost down,

 

[dantiff2]

HOOT! That’s fantastic. There’s only one other I’ve seen get results like that with the 450, and they go by a very similar name on a different site
Tell me, have you found annealing brass after that first or second firing to restore accuracy to the load specified above?

Also, any proven Winchester 296 or Alliant 2400 loads, perhaps with XTP bullets? Or good budget loads with FMJ bullets? Love the cartridge but trying to both use existing supplies and bring the cost down,

I have shot the pistol version of XTP's (250gn) with mild success. Went all the way up to 41.5 gn's of H110 with no pressure signs but velocity stalled out at 2330 fps at 39.5 gn's so the rest is just wasting powder. The fireball is absolutely awe inspiring from the muzzle brake of a 16" Ruger bolt gun!! As far as accuracy goes. 38 gn was the best at 1"@100 yards and only got worse the harder I pushed on them. Keep in mind that this is well beyond the velocity that the standard XTP is designed for. Upon inspecting the target i was able to find the copper jacket shed from the lead core laying in the dirt (in the back stop) so the fiber board was enough to separate the two at those speeds. Would not use these on any heavy game but should be great for predators!!
Dan

 

[H2OBUG]

H2O -

Howdy !

What sort of load are you considering, to start with ?

That's a nice, thoughtful build !


Regards,
357Mag

I have some 240 XTP Mags loaded over 37gr of 296 with a SRM primer. Also a 225 FTX over the 37gr of 296 SRM primer. Then some Winchester factory loads.
We will see how they do.

 

[dantiff2]

If you want to play around on the opposite end of the spectrum, big ole' heavy cast bullets at 1050 fps are really fun out of the 450. I do as CbaShooter said and size down 458 diameter bullets and load them over 10+ grains of Unique powder. My latest go were 405 gn RNFP 45-70 "go to" bullets (413 gn out of the mold with wheel weight lead). These went into one ragged hole at 50 yds with 10.7 gns unique and are as quiet as a 22 lr : )
Dan

 

[Hoot]

HOOT! That’s fantastic. There’s only one other I’ve seen get results like that with the 450, and they go by a very similar name on a different site
Tell me, have you found annealing brass after that first or second firing to restore accuracy to the load specified above?

Also, any proven Winchester 296 or Alliant 2400 loads, perhaps with XTP bullets? Or good budget loads with FMJ bullets? Love the cartridge but trying to both use existing supplies and bring the cost down,

If you're talking about the 450bushmaster.net site, I'm that guy. I moderate that forum as well as participate in it. I'm also shootenhoot on another site because hoot was already taken.

W296/H110 are also good powder choices though I prefer them for heavier bullets. Keep in mind that I run a 20" 1:24 AR platform and my loads will seem light compared to what a bolt action or break barrel system can safely handle. This caliber is plenty lethal without using bison weight bullets or squeezing every last fps out of you loads, given its large frontal area. The brass will last longer too if you don't stress them but then that's accepted wisdom for any caliber.

I tried Alliant 2400 with some 200gr bullets and it did well but the pressure stacks up on it quite quickly with heavier bullets. Its kinda fast for bullets above 200gr. The 240gr XTP Mag bullet is good performer over Lil Gun and the 300 XTP Mag does well with W296/H110 if you like heavier hitters.

WRT annealing. I did some testing and wrote up the results on the 450b site comparing annealed and un-annealed cases and I could not see any improvement in groups with 2-F brass. Neck tension rules the day in this caliber. The more you can get, the more consistent your results. Keep in mind this caliber sometimes adheres to rules that differ from our precision bottleneck caliber mantra.

Hoot

 

[Mauser06]

Hoot, nice to see ya here! Your posts on the other forum helped me navigate 450bm loading.


Nice looking rig you got h20bug!

I settled with a 250gr TTSX with lil gun around 2350. (Its a m700 bolt) Cant remember the powder charge off the top of my head. Barrel is 18" and twisted faster than needed. Shoots big ragged holes.


My rifle is just over 6lbs so she's hard to hang onto. I didn't see pressure signs. But recoil was getting obnoxious...and I don't need more.

Shot a buck with it this past season. He fell straight to the ground. Bullet put a nice entrance hole in a tree behind him



I too was curious about annealing the mouth. I've never loaded straight walls before so I have no idea if it's good or bad or what.

Fun round. I like heavy hitters. My hunting is short range stuff.

 

[Cbashooter]

If you want to play around on the opposite end of the spectrum, big ole' heavy cast bullets at 1050 fps are really fun out of the 450. I do as CbaShooter said and size down 458 diameter bullets and load them over 10+ grains of Unique powder. My latest go were 405 gn RNFP 45-70 "go to" bullets (413 gn out of the mold with wheel weight lead). These went into one ragged hole at 50 yds with 10.7 gns unique and are as quiet as a 22 lr : )
Dan

You're going the same direction I am with this. Essentially about the same stuff I shoot with my low pressure 4570 and unique.

 

[H2OBUG]

I have some 240 XTP Mags loaded over 37gr of 296 with a SRM primer. Also a 225 FTX over the 37gr of 296 SRM primer. Then some Winchester factory loads.
We will see how they do.

After shooting these loads I will be bumping these to the 39gr range. The 37gr loads were pretty light. Zero pressure signs.

 

[Hoot]

If you're using QuickLoad to model for the 450b, I could have told you that for some unknown reason, it overestimates W296, by quite a lot. Not so with Lil Gun.

Hoot

 

[Mauser06]

If you're using QuickLoad to model for the 450b, I could have told you that for some unknown reason, it overestimates W296, by quite a lot. Not so with Lil Gun.

Hoot

Hoot, since you're here and have mote experience than most of us....


Does the 450 bushmaster show normal pressure signs?? Sticky bolt, ejector swipe, etc?


Those fast burning powders scare me. I had an odd velocity curve if I recall correctly. Can't find my notes.


At 2350fps with a 250gr TTSX, I'm more than happy and my shoulder doesn't care to go higher. But I was sorta surprised to see that speed from an 18" faster twist.

 

[Hoot]

Hoot, since you're here and have mote experience than most of us....


Does the 450 bushmaster show normal pressure signs?? Sticky bolt, ejector swipe, etc?


Those fast burning powders scare me. I had an odd velocity curve if I recall correctly. Can't find my notes.


At 2350fps with a 250gr TTSX, I'm more than happy and my shoulder doesn't care to go higher. But I was sorta surprised to see that speed from an 18" faster twist.

The biggest factor in my experience pool is the fact that I only dealt with the 450b in an AR platform. Keep in mind that for about the first 8 years of its life, this caliber was only factory made in an AR platform. By the time bolt actions became common place, most bullet/powder combinations had already been experimented to death, albeit in AR platforms. Quantum leaps have been made since bolt action versions have become ubiquitous. That work was without my participation since I was totally satisfied with the lethality of this caliber at AR speeds and never bought a bolt action version since I didn't need one. Other members have picked up the bolt action torch and carried it on in their work. I have to defer to them for quality testing of their loads.

The only reliable, excessive pressure sign in the AR was Case Head Growth. It could be evident without flattened primers, imprinting or swipes. Cases usually started out around .4950 at their largest diameter point. After one trip through the excessive pressure weeds, they would mic at .5005. Next excessive trip, .5010, Next .5015 and maybe you could get one more reloading cycle, maybe not. My particular AR's chamber would no longer accept them after they reached .5017. Swipes were generally considered an indicator of the timing being off and imprinting was an indicator of too slow a rise in pressure, though it could also be the result of excessive pressure but usually accompanied by excessive CHG. Running them at excessive pressure through multiple reloading cycles usually resulted in cases that would no longer chamber, despite full length resizing. I'm not sure how this plays out with bolt actions though I feel safe in saying that pushing a 250gr to 2350, even from an 18 inch barrel, is not pushing your luck, unlike your shoulder.

Bottom line: Most of my historical efforts mainly benefit AR operators.

Hoot

 

[Mauser06]

Thanx Hoot! Didn't realize all your testing was from ARs. Your posts on the bushmaster forums helped me get going.

Fun round to load and shoot. I had a ball playing with milder loads and cheaper bullets.


The 250gr TTSX is has been awesome thus far. I also started loading the bullets in a sabot in my Encore inline. The exit hole it put in a coyote was amazing.

 

[JEFFPPC]

I have shot the pistol version of XTP's (250gn) with mild success. Went all the way up to 41.5 gn's of H110 with no pressure signs but velocity stalled out at 2330 fps at 39.5 gn's so the rest is just wasting powder. The fireball is absolutely awe inspiring from the muzzle brake of a 16" Ruger bolt gun!! As far as accuracy goes. 38 gn was the best at 1"@100 yards and only got worse the harder I pushed on them. Keep in mind that this is well beyond the velocity that the standard XTP is designed for. Upon inspecting the target i was able to find the copper jacket shed from the lead core laying in the dirt (in the back stop) so the fiber board was enough to separate the two at those speeds. Would not use these on any heavy game but should be great for predators!!
Dan

I also shoot the 250xtp with H110 39.5 grains cut the groups in my Mossberg Patriot more than in half. It's now an inch or under at 100 and 2 in at 200. I have shoot 2 large bucks, both ran 25 yards and fell. I did install a muzzle brake, it's a kicker.

 

[Hoot]

All my deer hunting for the last 40yrs has been up in the boreal forest of northern MN. I've had a total of 1 shot at 75yds and the rest 50 or under. My go-to recipe is the Barnes 200gr XPB, (the pointier one listed for the 460 S&W) over 41gr Lil Gun and Rem 7 1/2. 2500fps from my 20" 1:24 barrel and performs like this into sequential milk jugs full of water. Those petals are like copper Ginsu knives.

I used to use the 200 FTX, also at 2500fps, but I didn't like spitting out bits of lead when eating my venison and wondering how much I missed. Whitetails aren't hard to kill, 200gr with this frontal area is plenty lethal.

Hoot