You can find a wide variety of buffer weights and springs available for your AR-15 rifle. The quick points provided below can help you figure out which option would be the best buffer option for your gun.
Buffer weight is central to ensure that the rifle operates smoothly and that the rest of the parts last longer. Even the recoil impulse can be minimized if you adjust the buffer the right way. For your AR 15, you will want to check factors including the gas port size, gas system length as well as the ammunition you plan on using. Whether or not you’ll be using a suppressor also have bearing on these factors. Variations in weight include 3 oz steel carbines (three steel weights), 3.8 oz H1 (two steel and one tungsten weights), 4.6 oz H2 (one steel and two tungsten weights), 5.6 oz H3 (three tungsten weights), and 5.0 oz rifle buffer (five steel weights).
When it comes to the sizes of buffers, the two main ones to be looking at are carbine length and rifle length (the two are not interchangeable). Carbine length buffers are shorter than rifle length ones, with the latter mainly used for A2 buffer tubes on fixed stock ARs. The difference in length is meant to bring in extra space to the rifle buffer tube. Carbine length buffers, meanwhile, are ideal for use with collapsible socks that have carbine buffer tubes.
These may all look similar at first sight, but they are not, and you’ll definitely notice changes in rifle functionality after trying out different options. The diameters of carbine springs are all exactly the same though; what differs is the length. A standard spring for a carbine would stretch to around 10.5” and contain about 38 coils, while one for a rifle would be around 12.75 inches long and have either 41 or 42 coils. If you notice a “twang” sound when firing, you need to understand that the buffer spring is rubbing up against the interior of the buffer tube. This noise can be brought down by choosing a smoother surfaced spring, or adding a special, more lubricous finish.
Ultimately, you should let your needs guide you as to what buffer springs to choose as well as which buffer weight to use. This should ensure that you can shoot like a pro the next time you visit the firing range.