Welcome! Please take a minute to introduce yourself.

First things first - AR-10(T)300RSAUM bolt needed.

More
10 years 2 months ago #41740 by Petander
First things first - AR-10(T)300RSAUM bolt needed. was created by Petander
Hello forum and greetings from Finland .

As you can see I need a new 300RSAUM bolt and a gunsmith to check what made this happen at slightly over 1000 rounds.

I have had this rifle for a year now and to be honest the accuracy never got to where I thought it should be at, we may have had a problem all the way . I just got a reply from ArmaLite, they are working on a solution... but they can´t promise a bolt yet.



Do you know of a 300RSAUM bolt for sale ?


Thank you very much, Markku Petander , a retired rocker @ guitar hero from Finland , now digging deep in the long range ballistics.
This image is hidden for guests.
Please log in or register to see it.

Please Log in or Create an account to join the conversation.

More
10 years 2 months ago #41741 by Siscowet
Replied by Siscowet on topic First things first - AR-10(T)300RSAUM bolt needed.
Ouch! And welcome! I have always wanted to visit your country. You might send our member SOC a private message by looking him up in the direcctory and typing a message in the box. He is very knowledgeable about the 300 RSAUM and might be able to direct you to one. Good luck.

Please Log in or Create an account to join the conversation.

More
10 years 2 months ago #41749 by MTM
Replied by MTM on topic First things first - AR-10(T)300RSAUM bolt needed.
Welcome to the forum. Good luck on getting your bolt. Should you see Mika Hakkinen say hello for me....

Please Log in or Create an account to join the conversation.

More
10 years 2 months ago - 10 years 2 months ago #41750 by Petander
Replied by Petander on topic First things first - AR-10(T)300RSAUM bolt needed.
Excellent, thank you.

Should you see Ted Nugent say hello for me...

EDIT:


Mario @ ArmaLite actually replied to me now , I take this as a good sign. They are working on a solution - no bolts in stock of course.
Last edit: 10 years 2 months ago by Petander. Reason: ArmaLite contact while typing.

Please Log in or Create an account to join the conversation.

More
10 years 2 months ago #41751 by jtallen83
Replied by jtallen83 on topic First things first - AR-10(T)300RSAUM bolt needed.

Petander wrote: Excellent, thank you.

Should you see Ted Nugent say hello for me...

EDIT:


Mario @ ArmaLite actually replied to me now , I take this as a good sign. They are working on a solution - no bolts in stock of course.


Your in good hands, I'd bet they can and will help solve the issue.

Please Log in or Create an account to join the conversation.

More
10 years 2 months ago #41754 by Petander
Replied by Petander on topic First things first - AR-10(T)300RSAUM bolt needed.
I hope so.

This was a bumpy ride , I got this rifle a year ago with an old Zeiss on top of it. I tried load after load, range trip after another... and it just never grouped consistently good. Wasted lots of new brass which is impossible to find around here. Now , about a month ago I finally understood it was the scope which is being repaired in Germany right now. But still, even with different scopes... I was not getting consistency which means there always was a 3 or 4" 100 meter group for some unexplained reason every now and then. Not only me , other shooters as well.

My main long range rifle being a T3 Tac 300WM, it´s not even possible to make it group over 1" / 100m with ANY bullet / powder combination really. About 3" is a normal 300 meter / five round group for most factory hunting ammo , handloads I can get 1" or better with several bullets. 220 Scenar gave us 34 mm at 600 meters... not me shooting but my load... so you get the idea of my accuracy standards. But even one MOA is just fine if it is consistent and I can tust it, I was kinda expecting that from this Armalite. There may be something else wrong... I mean , is the next bolt going to break after 1000 rounds as well?

Please Log in or Create an account to join the conversation.

More
10 years 2 months ago #41776 by MrMarty51
Replied by MrMarty51 on topic First things first - AR-10(T)300RSAUM bolt needed.
Lets hope not, and, Welcome to the forum. :welcome:
Also hoping the groupings gets better.

Please Log in or Create an account to join the conversation.

More
10 years 2 months ago - 10 years 2 months ago #41782 by Petander
Replied by Petander on topic First things first - AR-10(T)300RSAUM bolt needed.
Thank you - the rifle is being examined as we type.

I tried about a dozen bullets and four powders during the year. 185 VLD , 185 Scenar, 220 Hammerhead and 175 Sierra MK come to mind as good ones... sometimes.

VV N560 and N550 work well and are easy to work up , pressure-wise . N160 is fine but won´t give you full velocities.

But this was supposed to be a nice side projest... which ended up being almosta a full time dayjob with less and less "fun" anymore . I can´t give up on this now , having ordered lots of brass etc.

My actual measurements, QuickLoad observations and chrono results match Nosler´s published data very well :

www.nosler.com/300-remington-short-action-ultra-magnum/


But what causes an AR to break at this low a round count ? I have outshot one Marlin 1895 45-70 but it took some 5000 rounds before the "Marlin Jam" rose it´s ugly head. With an AR you can fire 1000 rounds in a couple of range trips.

EDIT: 185 Lapua Mira was excellent,too. I chronoed ten rounds once and they all were within a couple of fps . Sometimes it also grouped well but only sometimes...
Last edit: 10 years 2 months ago by Petander. Reason: Added one bullet.

Please Log in or Create an account to join the conversation.

More
10 years 2 months ago #41783 by Siscowet
Replied by Siscowet on topic First things first - AR-10(T)300RSAUM bolt needed.
Have you had your specific barrel chamber measured? I am wondering if your headspace might be excessive. The farther away from the rifling grooves the bullet is when it is chambered, the greater potential for variations in accuracy. Or it may very well be that the defective bolt was not seating the whole cartridge completely in the chamber. That could very well affect accuracy and lead to the bolts early failure as well. I assume you have inspected the chamber for any potential flaws or visible variations that might have led to incomplete cartridge seating, while still allowing the bolt to lock into firing position. That would be rare to find that combination, but just a thought. Good luck and keep us informed.

Please Log in or Create an account to join the conversation.

More
10 years 2 months ago #41801 by Petander
Replied by Petander on topic First things first - AR-10(T)300RSAUM bolt needed.
When I got the rifle my main concern was feeding and overall reliability. So we checked the dimensions back and forth for a proper cartridge / brass size and length. I even have a shellholder that lets me resize too much as well , obviously a bad thing to do. It´s a relatively thin line in between not enough resize and too much , we stayed on the safe side. But I can only guess whether the bolt lock has always been totally complete or not - too large rounds didn´t fire but well... just a tad more resize and all was fine. Brass is good for 4-5 reloads. I trim it all, twice.

The rifle is being examined for whatever defects there may be , they are also checking out different possibilities for a temporary bolt fix . That being a DPMS carrier / bolt machined to 300RSAUM.

Please Log in or Create an account to join the conversation.