AR 300 win mag - AR15.COM

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Posted: 7/20/2017 7:43:41 AM EST

I know Omen and Falker make these. However at a $5000 price tag I was out of the running.

So here is my question, is it possible to get a billet receiver that is extended? That seems to be the hardest part to get so far.

Once I can get that or even find a cnc machinist to make it, the rest will fall in line. Am I being to simplistic in my idea, or will the cost of parts still be up to that 5k?

Posted: 7/21/2017 4:16:12 AM EST

[#1]

Here is another.
http://onlylongrange.com/bn36-long-range-assassin-300-win-mag-7mm-rem-mag/
Sure, you could make one from scratch, but it'd be a lot more than the lower. I suspect the upper, even the bcg and buffer must need to be longer.

Posted: 7/21/2017 10:07:33 AM EST

[#2]

I find semi auto gets really complicated when the caliber gets larger. You have to use only certain loads (or brands) of ammo or else it will not feed properly. Plus you really want to reload when you get into these magnum calibers since the brass is going to get expensive. Semi autos tend to throw brass into places where you can't reach. My experience with AR10 basically says that it's too heavy and too much for things to go wrong, not to mention expensive.

This is really where you want bolt action.

Posted: 7/21/2017 1:13:40 PM EST

[#3]

It's not going to happen short of you having some sort of engineering background and spending much more than $5k in R&D.

This isn't just an issue of receivers. You'll need a barrel with a correctly sized extension for what is going to be a custom bolt. Bolt Carrier is going to have to be custom as well to accommodate the additional receiver length.

What mags will you use? Do you understand how everything relates together when it comes to figuring out the exact placement and tolerances for the carrier bore, magwell, FCG pocket, etc.?

If it was as easy as you seem to think (paying a few hundred bucks to a machinist for him to just machine something for which there is no set standard), then a lot more than a small handful of companies would be making and selling them for cheaper than $5k.

Posted: 7/21/2017 1:46:15 PM EST

[#4]

You are really not going to find a good one for less that than $5K, we have couple of companies here in Montana that build them, but they are damn expensive and to have one machined would cost a whole bunch more!

Posted: 7/21/2017 6:26:05 PM EST

[#5]

For 5k, buy a mill and a lathe (both together will cost less than 5K if you choose wisely!), some toolings, and get one of these:

http://www.cncguns.com/forum/index.php?topic=1344.0

Costs around 200 dollars but the REALLY hard part is done. Then PTG bolts, and barrel (you can get factory barrel in 300 win mag for less than 50 dollars on ebay) and assorted other parts like trigger, bottom metal, stocks, etc.

Not a semi auto, or AR related, but it gets you a 300 win mag.

Alternatively you could just buy a Remington 700 BDL for around 400 dollars.

That 300 win mag AR is so expensive probably because of the amount of R&D involved. A Semi auto is more complicated, and to add length you have to add length to a bunch of parts, and then they gotta work without it falling apart.

But if I had 5K to spend on a single rifle I'd buy machines and make them myself... I get the machines, and the rifle is off the books.

Posted: 7/23/2017 11:40:24 AM EST

[#6]

It seems that there is more than what I anticipated. The info is good. I do reload and I do have a bolt action. It has been very accurate (out of the box rifle) and the mess ups are my own doing. I just was wondering about the semi. In regards to all the info above, and my lack of any kind of engineering I probably should stick with a bolt.

Thought that maybe I am missing out on something. I don't have a 700 but I do have a savage.

I did check out Noreen. Is it gig? They are half cost of the others.

Posted: 7/23/2017 11:56:55 AM EST

[#7]

By the way if you want to make a short action bolt action accept a long action cartridge (like 300 win mag) and don't mind being stuck to single shot, you could just install a 300 win mag barrel in a short action but in order to load, or unload the thing you have to remove the bolt completely, and drop the round in through the back.

It's certainly easier than making a short action semi auto 300 win mag. Though the same thing can be tried on an AR10 but your rifle will not be semi auto.

By the way have you thought of 300 WSM? They do make uppers for it but you have to modify your bolt to accept a magnum bolt face. I read they are fraught with problems though, like the bolt breaking because enlarging the bolt face made it weak...

http://www.ar15.com/forums/t_3_121/603810_AR_10_in_300_WSM__and_I_ve_got_problems__need_some_help.html

http://www.cncguns.com/forum/index.php?topic=2237.0

Posted: 7/23/2017 12:03:43 PM EST

[#8]

Quote History

Quoted:
It seems that there is more than what I anticipated. The info is good. I do reload and I do have a bolt action. It has been very accurate (out of the box rifle) and the mess ups are my own doing. I just was wondering about the semi. In regards to all the info above, and my lack of any kind of engineering I probably should stick with a bolt.

Thought that maybe I am missing out on something. I don't have a 700 but I do have a savage.

I did check out Noreen. Is it gig? They are half cost of the others.

View Quote

Noreen's is a great company, I have bought a lot of uppers and lowers from them over the years, their specialty is long range guns and they have developed pretty much everything on their own at their plant in Belgrade. They are proprietary guns and they are were you will have to get parts and magazines from, but I know a few guys that own them and are very happy with there guns.

Posted: 7/23/2017 12:18:16 PM EST

[#9]

Surprised no fanboys are promoting the weakling 6.5 Grendel yet!

Posted: 7/23/2017 12:24:04 PM EST

[#10]

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Quoted:
Surprised no fanboys are promoting the weekling 6.5 Grendel yet!

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The Grendel is a pipsqueak compared to a .300 WM

Posted: 7/23/2017 2:33:49 PM EST

[#11]

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Quoted:

The Grendel is a pipsqueak compared to a .300 WM

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Yes Sir the 300 brings it no argument there. It's just in the past anytime someone ask about a caliber somehow some blow hard gets a plug in for the Grendel. Sorry op not trying to get off track.

Posted: 7/23/2017 2:54:54 PM EST

[#12]

When I was on the tour, I asked them reloaders about the creedmore and the Grendel. In 1k yards they said it could be about the same. But after that...all WM

. So I decided that at that moment, might as well have the capabilities to go the distance if needed. So far it has been punching through half inch steel at 250 yards with sst. Thinking trying hp's one time. But, it was also a thought to take that punch to a semi model...then my capacity goes from three to five or ten.

So if I am building my own bolt now, what chases shout I get to with to mags? I heard they exist, but maybe that is a conversation for the precision section?

Posted: 7/23/2017 2:58:17 PM EST

[#13]

@ SR- 72: No problem. I Don't mind seeing the topic take different turns. I have been enjoying the depth of information.

Posted: 7/23/2017 2:59:18 PM EST

[#14]

Well, honestly it depends if it's worth the cost to you... I don't know how reliable they are but the WSM uppers all seemed to have feeding issues (as in ripping off the rim and having to pound the case out after each shot). I hoped the 300WM semi autos have solved that problem.

For 5k you could just have gone with 338 LM and be able to punch through body armor even at 1000 yards.

Posted: 7/23/2017 3:05:52 PM EST

[#15]

Quote History

Quoted:
Well, honestly it depends if it's worth the cost to you... I don't know how reliable they are but the WSM uppers all seemed to have feeding issues (as in ripping off the rim and having to pound the case out after each shot). I hoped the 300WM semi autos have solved that problem.

For 5k you could just have gone with 338 LM and be able to punch through body armor even at 1000 yards.

View Quote

I had thought of the WSM but I traded a 410 shotgun (was the wife's and it saw day once) and got an even trade for my WM, so I kinda stuck with it since it was an even trade. I wish I had 5k sitting around. I will be able to fund my gun fund better after I pay off debt

. For 5k, I would be really interested in a BMG

. Right now, I am happy to have extra just to load what I shoot.

I do like the LM though. It is a nice round.

Posted: 7/24/2017 4:04:19 PM EST

[#16]

Quote History

Quoted:
When I was on the tour, I asked them reloaders about the creedmore and the Grendel. In 1k yards they said it could be about the same. But after that...all WM

. So I decided that at that moment, might as well have the capabilities to go the distance if needed. So far it has been punching through half inch steel at 250 yards with sst. Thinking trying hp's one time. But, it was also a thought to take that punch to a semi model...then my capacity goes from three to five or ten.

So if I am building my own bolt now, what chases shout I get to with to mags? I heard they exist, but maybe that is a conversation for the precision section?

View Quote

The Grendel and the Creedmoor are not an even comparison. 6.5CM can keep up with 300WM until you get into 300WM's heavier 200gr+ loads and by the time you get into the 230gr VLD's 300WM is in 338LM territory.

As for gas guns in 300WM or even 6.5cm pressure will be an issue. For a 300wm you'll want to make sure that the gun can handle the pressure of the heavier 200-230gr loads since they are what gives the 300wm It's ELR capabilities. If you're cost minded you may want to look into a 6.5cm build on an Areo, I've been seeing uppers and other parts at great prices as of late and the 6.5cm is no slouch.

If you want to build a custom or mod your gun with a chasis then take a look at these companies, XLR, Manners, MDT, Accuracy International (chasis), & KRG.

Posted: 7/24/2017 5:29:52 PM EST

[#17]

I didn't even want to mess around with AR10's either. There's just so much fine balance between the weight of the BCG, the weight of the buffer, the power of the spring, the length of the gas tube, etc. that these all have to be balanced every time you change your load. Then you have the fact that the rifle throws expensive brass into never never land...

Then there's also the question that semi auto actions may not tolerate high pressure as well as a Remington or Weatherby action can... meaning shooting 220 grain bullets may end up damaging the rifle..

Some things are better off being bolt action or single shot.

Posted: 7/24/2017 10:23:00 PM EST

[#18]

Quote History

Quoted:

The Grendel and the Creedmoor are not an even comparison. 6.5CM can keep up with 300WM until you get into 300WM's heavier 200gr+ loads and by the time you get into the 230gr VLD's 300WM is in 338LM territory.

As for gas guns in 300WM or even 6.5cm pressure will be an issue. For a 300wm you'll want to make sure that the gun can handle the pressure of the heavier 200-230gr loads since they are what gives the 300wm It's ELR capabilities. If you're cost minded you may want to look into a 6.5cm build on an Areo, I've been seeing uppers and other parts at great prices as of late and the 6.5cm is no slouch.

If you want to build a custom or mod your gun with a chasis then take a look at these companies, XLR, Manners, MDT, Accuracy International (chasis), & KRG.

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I never intended for it to come across saying that it was a slouch. Sorry if it did. I have never used them. Going off Hornady's info (and I had already had several hundred rounds loaded), I thought I would stay wm. Just as it sits, to switch I would need a new rifle, mags, ammo, reloading dies and components. Plus start at zero rounds. It sounds like I can go higher grains with the wm.

Out of the mod stocks, which do you recommend? I Don't mind bolt action but the stock would allow me to get some mags for more capacity.

Posted: 7/24/2017 10:28:14 PM EST

[#19]

Quote History

Quoted:

Some things are better off being bolt action or single shot.

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this may be the time bolt is best. I know it works and I am not blowing parts.

Posted: 7/24/2017 10:44:38 PM EST

[#20]

The big win Mags are very much like an AR-10/LR-308, just... Uhhh More bigger-er.

They handle the heavy loads just fine as long as you are willing to live with the chamber for them. Mod-1 and Mod-0 come to mind for pressure in these platforms.

They will start dumping primers way way before you come close to over pressuring the system.

Posted: 7/25/2017 1:55:46 AM EST

[#21]

Quote History

Quoted:
I never intended for it to come across saying that it was a slouch. Sorry if it did. I have never used them. Going off Hornady's info (and I had already had several hundred rounds loaded), I thought I would stay wm. Just as it sits, to switch I would need a new rifle, mags, ammo, reloading dies and components. Plus start at zero rounds. It sounds like I can go higher grains with the wm.

Out of the mod stocks, which do you recommend? I Don't mind bolt action but the stock would allow me to get some mags for more capacity.

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No reason to apologise I didn't think you said anything negative about the CM, besides I like both cartridges anyways. I don't think you can go wrong with any of the chasis systems I listed. Hard to give another person advice on a chasis, they're very personal and will fit everyone differently. For me XLR's fit me and shoulder the best for me. Best to get out shoulder and look at some and see what you like and fits you best. If you don't have any shops near by that carry long range rifle items Cabelas sometimes will have used rifles that maybe in popular chasis systems and also carries a Bergara LRP rifle which rides in an XLR Element if you just want to see get a feel for the different chassis systems.

Posted: 7/27/2017 2:34:26 PM EST

[#22]

Noreen was the first to market with the production big bore ar's. Instead of asking why half the price why not ask why the others are over double? Gotta pay for the hot wife somehow!
For a production 300 Win AR Platform or the 7 Mag AR Platform its hard to compare when all the features are the same with the competition.
complete rifle
Noreen 300 Win and 7 Mag AR Platform

Billet upper and Lower set
Billet BN36 Upper and Lower Set

Posted: 7/27/2017 2:39:06 PM EST

[#23]

A vid shooting Noreen 300 Win AR Platform and switching uppers to 30-06 ar
Badassness

Posted: 7/27/2017 3:42:38 PM EST

[#24]

You could get this

http://onlylongrange.com/bn36-long-range-assassin-complete-upper-receiver/

then probably machine yourself a lower but I have no idea how the parts fit together or whether the fire control is anywhere near the same as milspec. They do sell 80% lowers but only for AR15 and AR10. Wouldn't hurt to ask if they can provide information on how to machine a lower...

Posted: 7/28/2017 8:46:16 PM EST

[#25]

Quote History

Quoted:
Noreen was the first to market with the production big bore ar's. Instead of asking why half the price why not ask why the others are over double? Gotta pay for the hot wife somehow!
For a production 300 Win AR Platform or the 7 Mag AR Platform its hard to compare when all the features are the same with the competition.
complete rifle
Noreen 300 Win and 7 Mag AR Platform

Billet upper and Lower set
Billet BN36 Upper and Lower Set

View Quote

Ehhh... Nothing against Noreen, as that is the target market for them, but they are very simple in design, and the cost of production is much lower. They lack gas adjustment for suppressor use also.

I don't know if NEMO was out at about the same time or before or what.

Posted: 7/28/2017 9:22:36 PM EST

[#26]

Quote History

Quoted:

Ehhh... Nothing against Noreen, as that is the target market for them, but they are very simple in design, and the cost of production is much lower. They lack gas adjustment for suppressor use also.

I don't know if NEMO was out at about the same time or before or what.

View Quote

NEMO has not been around even close to the amount of time that Noreen has been around, Nemo used to be here when I live, I see they have moved to ID now.

Posted: 7/28/2017 10:07:07 PM EST

[#27]

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NEMO has not been around even close to the amount of time that Noreen has been around, Nemo used to be here when I live, I see they have moved to ID now.

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Oh I know that, Noreen is a legend honestly, I was referring to the "Worlds First."

I work at NEMO Arms here in Idaho.

Posted: 7/28/2017 11:20:27 PM EST

[#28]

Quote History

Quoted:

Oh I know that, Noreen is a legend honestly, I was referring to the "Worlds First."

I work at NEMO Arms here in Idaho.

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NEMO makes a great gun, I have shot a few of their guns. I am just not into the big bore AR type weapons, I do have several long range bolt guns that I used to shoot in competition. Now a days I play with my 556 most of the the time, I have not picked up the bolt guns for a while.

Posted: 7/28/2017 11:36:19 PM EST

[#29]

RND Manufacturing does some oddball big AR based builds as well.

In the 90s they were doing matched CNC upper/lowers before anyone else. It is what JP Enterprises used for their top shelf guns.

Posted: 8/18/2017 2:14:49 PM EST

[#30]

You may want to look at the POF P300. looks like just over 3K. Their are more than a few pitfalls to the large auto loaders. As mentioned with the primers, along with beating up the ammo pretty bad. The guys that have it figured out have spent countless hours on this platform.

Posted: 8/23/2017 9:34:21 PM EST

[#31]

Been on and off for work. After looking at everything, I may stick with my bolt action...unless Nemo wants another field tester. I will do that for free

!

I do appreciate all the advice though. I did see a rpr at my lgs and it was a little over 1k. Had the tac stock but I would need all new stuff. It looked good though.

Posted: 8/24/2017 3:53:32 AM EST

[#32]

One advise if you go with bolt action...

Make the gun as heavy as you can possibly carry it, and/or put a compensator on the muzzle.

I just shot my homemade 300 win mag rifle, and it kicked HARD. Hard enough that I really do not want to shoot this more than 4 rounds. The gun was not too heavy and I think this contributed to the harsh recoil.

Posted: 8/24/2017 6:52:58 AM EST

[#33]

Quote History

Quoted:
One advise if you go with bolt action...

Make the gun as heavy as you can possibly carry it, and/or put a compensator on the muzzle.

I just shot my homemade 300 win mag rifle, and it kicked HARD. Hard enough that I really do not want to shoot this more than 4 rounds. The gun was not too heavy and I think this contributed to the harsh recoil.

View Quote

You probably need to lead the stock, which is what I used to do to my long range match guns.

Posted: 8/24/2017 8:54:24 AM EST

[#34]

Quote History

Quoted:
One advise if you go with bolt action...

Make the gun as heavy as you can possibly carry it, and/or put a compensator on the muzzle.

I just shot my homemade 300 win mag rifle, and it kicked HARD. Hard enough that I really do not want to shoot this more than 4 rounds. The gun was not too heavy and I think this contributed to the harsh recoil.

View Quote

I appreciate the advice. I do like the kick of my 300 (I am 6'4" and 225 lbs) and I feel that I really shot something! Maybe I am

. However, getting back on target and even holding the rifle still while on bi-pods is the biggest struggle. I can't get the darn thing to stop jumping with my heart beat. However, if I can eliminate the kick for quick re-acquisition, I want to do that. Is it cheaper to buy a barrel that is already threaded or to get it threaded? If getting it threaded, who do you recommend? Lastly, what compensator do you recommend?

I may not be able to get all of this done right away but I can use the advice. Thanks.

Posted: 8/24/2017 8:55:21 AM EST

[#35]

Quote History

Quoted:

You probably need to lead the stock, which is what I used to do to my long range match guns.

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What is leading the stock? I can't recall if I had ever heard that before. Thanks.

Posted: 8/24/2017 9:46:50 AM EST

[#36]

I'm assuming it meant adding lead weights to the stock to make it heavier so to reduce recoil and improve the firearm's stability.

Posted: 8/24/2017 1:04:26 PM EST

[#37]

Quote History

Quoted:
I'm assuming it meant adding lead weights to the stock to make it heavier so to reduce recoil and improve the firearm's stability.

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Yes, that is what I used to do with my match rifles, and I have a buddy that bought a Armalite AR15 from the National Guard Armory here and it came with several different lead weights to add to the stock and make it more stable., it can calm recoil down quite a bit.

Posted: 8/24/2017 1:43:52 PM EST

[#38]

I don't know but it doesn't seem like you can add weights to a M4 type telescoping stock... it would work on the A2 stock because it has a compartment in it for cleaning kits. While my A1 upper has light recoil it seems enough for me to lose target just a little bit.

Posted: 8/24/2017 2:12:15 PM EST

[#39]

Quote History

Quoted:
I don't know but it doesn't seem like you can add weights to a M4 type telescoping stock... it would work on the A2 stock because it has a compartment in it for cleaning kits. While my A1 upper has light recoil it seems enough for me to lose target just a little bit.

View Quote

His Armalight is an A2 Style and the stock has actual spots to put the weights in it, it is the only one that I have ever seen, the furniture on it is OD green, it is a nice rifle, but really heavy when you load it with the weights..

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