I am going to venture off into the large frame AR world. What is the most accurate receiver set to start a project with?
Thanks
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Large frame AR receiver set question
- Thread starter Smitty192
- Start date
MEGA, Falkor, 2A Armament are top of the list. I personally use MEGA for all my large frame precision builds but can't go wrong with any of those.
Thanks for the info. Is the receiver set critical in the accuracy equation? Is lapping the upper receiver face (where the barrel meets the receiver) of any benefit?
I have talked to JP before and they mentioned that was standard for large frame AR product. How would the average person go about that? Do the receivers you mentioned above need to have the barrel thermo fit to the receiver? Or is a slightly oversized barrel extension?
I wouldnt call it standard, only the top tier receiver makers undersize their barrel extension area on the upper for thermofitting in my experience. Example, the Aero M5 is not a thermofit upper. MEGA is a thermofit upper.
Here's what you do to thermofit the barrel:
1) Put the upper on your reaction rod (if you dont have one I highly recommend you pick up a Geissele reaction rod).
2) Heat the front of the receiver up with a heat gun 360 degrees around the area where the barrel extension will slide in for a good 60-90 seconds. If your not using a true heat gun on high you may need to heat longer to get it up to temp. What your doing is getting the metal to expand slightly so the barrel extension slips right in (it will not slip in at all before you heat it).
3) Apply either Loctite 609 or Rocksett liberally to the entire barrel extension (Not the inside of the upper). I use 609 but have used Rocksett for years as well. Either is fine.
4) Quickly push the barrel extension with the 609 on it into the upper receiver all the way till its fully inserted.
5) Install and torque the barrel nut
6) Wipe away any 609 or Rocksett that has squeezed out during torquing the barrel nut. Check both inside of the upper and front of the receiver around the barrel nut.
7) I usually now let it sit overnight then finish building it out and testing the following day.
A few tips. Make sure the upper is fully heated by inserting the barrel extension without any 609 on it to ensure the barrel is going to slip all the way in. When you have it to where the barrel slips all the way in pull the barrel out, quickly apply 609 or Rocksett and push the barrel in quickly. Dont slowly push the barrel in or let the upper cool after removing the heat gun. Also the hot upper will dry that 609 or Rocksett instantly and the barrel will be stuck half way in or wherever you have it so make sure you push it straight in all the way. If you dont you will have to hit it with heat, pull it out, clean off the barrel and the inside of the upper and start over. Its fine but just messy and more work if you do that.
You have now thermofit your upper to your barrel for a rock solid fit. Also remember, if you ever want to remove your barrel you will need to heat the front of the upper receiver up till the barrel pulls out. It wont come out without heating it up again.
Here's what you do to thermofit the barrel:
1) Put the upper on your reaction rod (if you dont have one I highly recommend you pick up a Geissele reaction rod).
2) Heat the front of the receiver up with a heat gun 360 degrees around the area where the barrel extension will slide in for a good 60-90 seconds. If your not using a true heat gun on high you may need to heat longer to get it up to temp. What your doing is getting the metal to expand slightly so the barrel extension slips right in (it will not slip in at all before you heat it).
3) Apply either Loctite 609 or Rocksett liberally to the entire barrel extension (Not the inside of the upper). I use 609 but have used Rocksett for years as well. Either is fine.
4) Quickly push the barrel extension with the 609 on it into the upper receiver all the way till its fully inserted.
5) Install and torque the barrel nut
6) Wipe away any 609 or Rocksett that has squeezed out during torquing the barrel nut. Check both inside of the upper and front of the receiver around the barrel nut.
7) I usually now let it sit overnight then finish building it out and testing the following day.
A few tips. Make sure the upper is fully heated by inserting the barrel extension without any 609 on it to ensure the barrel is going to slip all the way in. When you have it to where the barrel slips all the way in pull the barrel out, quickly apply 609 or Rocksett and push the barrel in quickly. Dont slowly push the barrel in or let the upper cool after removing the heat gun. Also the hot upper will dry that 609 or Rocksett instantly and the barrel will be stuck half way in or wherever you have it so make sure you push it straight in all the way. If you dont you will have to hit it with heat, pull it out, clean off the barrel and the inside of the upper and start over. Its fine but just messy and more work if you do that.
You have now thermofit your upper to your barrel for a rock solid fit. Also remember, if you ever want to remove your barrel you will need to heat the front of the upper receiver up till the barrel pulls out. It wont come out without heating it up again.
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Thank you for taking the time to share all of this. This is great information and I appreciate your input.
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